|
Home > Archive > Alternative Power sources > December 2005 > Next Meeting of Inverters Anonymous?
You are viewing an archived Text-only version of the thread.
To view this thread in it's original format and/or if you want to reply to
this thread please [click here]
| Author |
Next Meeting of Inverters Anonymous?
|
|
| Ulysses 2005-12-16, 10:21 pm |
| I have a problem. I keep blowing up inverters. Then I find myself on eBay
looking for more to buy. I am running a 63 Amp alternator with a 4 HP
engine. It still has the built-in voltage regulator. It is connected to an
85 Ah deep cycle battery. I have had, so far, 4 different inverters ranging
from 300-800 watts connected to it which I was using to power battery
chargers mainly. One of the battery chargers is a Vector 40 amp Smart
Charger. The other is a Schumacher 15 amp automatic charger that is no
longer automatic. I thought it would be safe to power the 15 amp charger
with a 300 watt MSW inverter as it usually draws less than 200 watts.
Before it died the ammeter needle was bouncing up and down. I thought the
problem was a loose connection inside the charger. I checked all
connections and then tried another 300 watt MSW inverter. The first one now
thinks that either the battery is too low or it is overloaded. It almost
works. The second one shorted out and blew the fuse. It may be possible to
repair but it'll have to wait. Most recently my 800 watt Vector SST
inverter quit working while powering the two chargers. It is under
warranty. It now says "OL" all the time. I can't really include the Wagan
700 watt inverter in this scenerio because it was destroyed by overvoltage
when I connected it to the alternator without a battery in parallel. I
replaced 5 or 6 capacitors and it seemed ok until I used it briefly to power
the battery chargers and then accidently ran a coffee maker with it which no
doubt was a little bit too much for it.
So, my question is can anyone tell me why a battery charger would cause the
failure of so many inverters? I suspect the Schumacher charger to be the
problem and will not use it on my next inverter but is it possible the
Vector Smart Charger is causing the problem?
I need to charge two sets of batteries that are about 100 feet apart.
Charging directly from the alternator will work fine for my main battery
bank but I still need to charge the other one somehow. So far the built-in
voltage regulator in the alternator keeps up with the inverters demand and
keeps the deep cycle battery charged and apparently is not overcharging it.
I have been looking at the different charge controller circuits so I can
have the option of charging directly but I'm afraid the battery life will
diminish without the regulated 3-stage charging I also like the option of
using the setup as an AC generator but I'm tired of destroying inverters.
Please help.
BTW I found a 1250 watt Inverter for only $50. Anyone ever heard of Homier
aka HDC? They have few specs for it.
http://cgi.ebay.com/ws/eBayISAPI.dl...99174&ssPageNam
e=STRK:MEWA:IT#ebayphotohosting
..
| |
| Harry Chickpea 2005-12-16, 11:21 pm |
| "Ulysses" <therealulysses@yahoo.com> wrote:
>I have a problem. I keep blowing up inverters. Then I find myself on eBay
>looking for more to buy. I am running a 63 Amp alternator with a 4 HP
>engine. It still has the built-in voltage regulator. It is connected to an
>85 Ah deep cycle battery. I have had, so far, 4 different inverters ranging
>from 300-800 watts connected to it which I was using to power battery
>chargers mainly. One of the battery chargers is a Vector 40 amp Smart
>Charger. The other is a Schumacher 15 amp automatic charger that is no
>longer automatic. I thought it would be safe to power the 15 amp charger
>with a 300 watt MSW inverter as it usually draws less than 200 watts.
>Before it died the ammeter needle was bouncing up and down. I thought the
>problem was a loose connection inside the charger. I checked all
>connections and then tried another 300 watt MSW inverter. The first one now
>thinks that either the battery is too low or it is overloaded. It almost
>works. The second one shorted out and blew the fuse. It may be possible to
>repair but it'll have to wait. Most recently my 800 watt Vector SST
>inverter quit working while powering the two chargers. It is under
>warranty. It now says "OL" all the time. I can't really include the Wagan
>700 watt inverter in this scenerio because it was destroyed by overvoltage
>when I connected it to the alternator without a battery in parallel. I
>replaced 5 or 6 capacitors and it seemed ok until I used it briefly to power
>the battery chargers and then accidently ran a coffee maker with it which no
>doubt was a little bit too much for it.
>
>So, my question is can anyone tell me why a battery charger would cause the
>failure of so many inverters? I suspect the Schumacher charger to be the
>problem and will not use it on my next inverter but is it possible the
>Vector Smart Charger is causing the problem?
Typically, chargers are designed to use the top portion of the input
sine wave. The charger expects 164 volts +- at peak. A MSW inverter
doesn't reach anywhere near this voltage, topping out at 120 volts or
less. Even some smaller generators under load will "flat-top" and not
deliver the wave the charger wants.
Are your small inverters seeing the chargers as a huge load and
plotzing? Dunno, but it seems like a possibility. A true sine wave
inverter would be a costly solution, but less costly than burning up
multiple MSW inverters.
>I need to charge two sets of batteries that are about 100 feet apart.
>Charging directly from the alternator will work fine for my main battery
>bank but I still need to charge the other one somehow. So far the built-in
>voltage regulator in the alternator keeps up with the inverters demand and
>keeps the deep cycle battery charged and apparently is not overcharging it.
>I have been looking at the different charge controller circuits so I can
>have the option of charging directly but I'm afraid the battery life will
>diminish without the regulated 3-stage charging I also like the option of
>using the setup as an AC generator but I'm tired of destroying inverters.
>
>Please help.
One option is to make a version of the old rotary converter used by
theatres and trolley lines. At the far end of your line, you power a
small electric motor, which in turn powers a second small alternator,
which charges your battery.
FWIW, For a single deep-cycle battery, your alternator setup has the
potential to cause problems. If you go down to an 80% DoD on the
battery, and then recharge, using the alternator without any other
load, or current limitation, the charge rate will be far faster than
the optimal C/20 or slower rate that deep-cycles like. An 85aH
battery C/20 rate is less than 5 amps. Even a C/10 rate is only
roughly 8.5 amps.
However, if you only use the top 20% of the battery capacity, the
voltage regulator and battery resistance will limit the charge current
and your battery may be fine. I'd absolutely drop out the load on the
battery if it reached down to 12 volts. Otherwise, you'll be like me,
hoping for some magic method to restore capacity in batteries that
were charged too fast to many times.
>
| |
| Steve Spence 2005-12-16, 11:21 pm |
| Ulysses wrote:
> I have a problem. I keep blowing up inverters. Then I find myself on eBay
> looking for more to buy. I am running a 63 Amp alternator with a 4 HP
> engine. It still has the built-in voltage regulator. It is connected to an
> 85 Ah deep cycle battery. I have had, so far, 4 different inverters ranging
> from 300-800 watts connected to it which I was using to power battery
> chargers mainly. One of the battery chargers is a Vector 40 amp Smart
> Charger. The other is a Schumacher 15 amp automatic charger that is no
> longer automatic. I thought it would be safe to power the 15 amp charger
> with a 300 watt MSW inverter as it usually draws less than 200 watts.
> Before it died the ammeter needle was bouncing up and down. I thought the
> problem was a loose connection inside the charger. I checked all
> connections and then tried another 300 watt MSW inverter. The first one now
> thinks that either the battery is too low or it is overloaded. It almost
> works. The second one shorted out and blew the fuse. It may be possible to
> repair but it'll have to wait. Most recently my 800 watt Vector SST
> inverter quit working while powering the two chargers. It is under
> warranty. It now says "OL" all the time. I can't really include the Wagan
> 700 watt inverter in this scenerio because it was destroyed by overvoltage
> when I connected it to the alternator without a battery in parallel. I
> replaced 5 or 6 capacitors and it seemed ok until I used it briefly to power
> the battery chargers and then accidently ran a coffee maker with it which no
> doubt was a little bit too much for it.
>
> So, my question is can anyone tell me why a battery charger would cause the
> failure of so many inverters? I suspect the Schumacher charger to be the
> problem and will not use it on my next inverter but is it possible the
> Vector Smart Charger is causing the problem?
>
> I need to charge two sets of batteries that are about 100 feet apart.
> Charging directly from the alternator will work fine for my main battery
> bank but I still need to charge the other one somehow. So far the built-in
> voltage regulator in the alternator keeps up with the inverters demand and
> keeps the deep cycle battery charged and apparently is not overcharging it.
> I have been looking at the different charge controller circuits so I can
> have the option of charging directly but I'm afraid the battery life will
> diminish without the regulated 3-stage charging I also like the option of
> using the setup as an AC generator but I'm tired of destroying inverters.
>
> Please help.
>
> BTW I found a 1250 watt Inverter for only $50. Anyone ever heard of Homier
> aka HDC? They have few specs for it.
>
> http://cgi.ebay.com/ws/eBayISAPI.dl...99174&ssPageNam
> e=STRK:MEWA:IT#ebayphotohosting
> .
>
>
you aren't connecting ground and neutral anywhere are you? I paid $269
for my 2500 watt unit. AC Delco from BJ's Wholesale.
Why are you using a battery to power an inverter, feeding a charger to
charge a battery?
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| Steve Spence 2005-12-16, 11:21 pm |
| Steve Spence wrote:
> Ulysses wrote:
>
>
> you aren't connecting ground and neutral anywhere are you? I paid $269
> for my 2500 watt unit. AC Delco from BJ's Wholesale.
>
>
> Why are you using a battery to power an inverter, feeding a charger to
> charge a battery?
>
>
Never mind, I found the answer in the last part of your email, I missed
the distance issue the first time. I guess investing in a big set of
cables and connecting the batteries directly is out of the question ....
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| Ulysses 2005-12-17, 12:21 am |
|
"Harry Chickpea" <hchickpeaREMOVEME@hotmail.com> wrote in message
news:43a97d6e.47438590@localhost...
> "Ulysses" <therealulysses@yahoo.com> wrote:
>
eBay[color=darkred]
an[color=darkred]
ranging[color=darkred]
the[color=darkred]
now[color=darkred]
to[color=darkred]
Wagan[color=darkred]
overvoltage[color=darkred]
power[color=darkred]
no[color=darkred]
the[color=darkred]
>
> Typically, chargers are designed to use the top portion of the input
> sine wave. The charger expects 164 volts +- at peak. A MSW inverter
> doesn't reach anywhere near this voltage, topping out at 120 volts or
> less. Even some smaller generators under load will "flat-top" and not
> deliver the wave the charger wants.
I suspected there might be something to that. I'd asked somewhere before
about this but I guess I didn't know precisely what question to ask.
>
> Are your small inverters seeing the chargers as a huge load and
> plotzing? Dunno, but it seems like a possibility. A true sine wave
> inverter would be a costly solution, but less costly than burning up
> multiple MSW inverters.
>
built-in[color=darkred]
and[color=darkred]
it.[color=darkred]
of[color=darkred]
>
> One option is to make a version of the old rotary converter used by
> theatres and trolley lines. At the far end of your line, you power a
> small electric motor, which in turn powers a second small alternator,
> which charges your battery.
Interesting idea. Sound kinda redundant but I'll think about it.
>
> FWIW, For a single deep-cycle battery, your alternator setup has the
> potential to cause problems. If you go down to an 80% DoD on the
> battery, and then recharge, using the alternator without any other
> load, or current limitation, the charge rate will be far faster than
> the optimal C/20 or slower rate that deep-cycles like. An 85aH
> battery C/20 rate is less than 5 amps. Even a C/10 rate is only
> roughly 8.5 amps.
The larger battery bank I'm charging is 440 Ah so even if it was charging at
the full 63 amps it would not be an extreme overcharge but I prefer keeping
it around 40 amps max. My smaller battery bank is 220 Ah.
>
> However, if you only use the top 20% of the battery capacity, the
> voltage regulator and battery resistance will limit the charge current
> and your battery may be fine. I'd absolutely drop out the load on the
> battery if it reached down to 12 volts. Otherwise, you'll be like me,
> hoping for some magic method to restore capacity in batteries that
> were charged too fast to many times.
That's why I like the Vector charger because it seems to know how fast to
charge batteries. Even if someone without knowing any better set it for 40
amps on a 100 Ah battery it would probably not exceed 15 Amps. Plus it's a
3 stage charger and can get them almost to 100% in a reasonable amount of
time.
>
>
| |
| Ulysses 2005-12-17, 1:21 am |
|
"Steve Spence" <sspence@green-trust.org> wrote in message
news:43a37bdd$1_2@newsfeed.slurp.net...
> Ulysses wrote:
eBay[color=darkred]
to an[color=darkred]
ranging[color=darkred]
charger[color=darkred]
the[color=darkred]
now[color=darkred]
almost[color=darkred]
possible to[color=darkred]
Wagan[color=darkred]
overvoltage[color=darkred]
power[color=darkred]
which no[color=darkred]
the[color=darkred]
the[color=darkred]
built-in[color=darkred]
and[color=darkred]
it.[color=darkred]
will[color=darkred]
of[color=darkred]
inverters.[color=darkred]
Homier[color=darkred]
http://cgi.ebay.com/ws/eBayISAPI.dl...99174&ssPageNam[color=darkred]
>
> you aren't connecting ground and neutral anywhere are you?
I don't see how I could be but I'll check it.
I paid $269
> for my 2500 watt unit. AC Delco from BJ's Wholesale.
>
>
> Why are you using a battery to power an inverter, feeding a charger to
> charge a battery?
>
Ultimately I would prefer to be able to feed an inverter without having a
battery in parallel with the alternator but having the battery allows the DC
generator to be used when the engine is not running. I'm looking at the
battery as part of the generator as absurd as it is to be using a battery to
charge a battery. Eventually I'll probably build the field controller as
shown at: http://www.homepower.com/files/mark8.pdf
and see if I can get it work but I'll probably blow something else up.
>
> --
> Steve Spence
> Dir., Green Trust, http://www.green-trust.org
> Contributing Editor, http://www.off-grid.net
> http://www.rebelwolf.com/essn.html
| |
| Pete C 2005-12-17, 1:21 pm |
| On Fri, 16 Dec 2005 17:39:23 -0800, "Ulysses"
<therealulysses@yahoo.com> wrote:
>I have a problem. I keep blowing up inverters. Then I find myself on eBay
>looking for more to buy. I am running a 63 Amp alternator with a 4 HP
>engine. It still has the built-in voltage regulator. It is connected to an
>85 Ah deep cycle battery. I have had, so far, 4 different inverters ranging
>from 300-800 watts connected to it which I was using to power battery
>chargers mainly. One of the battery chargers is a Vector 40 amp Smart
>Charger. The other is a Schumacher 15 amp automatic charger that is no
>longer automatic. I thought it would be safe to power the 15 amp charger
>with a 300 watt MSW inverter as it usually draws less than 200 watts.
>Before it died the ammeter needle was bouncing up and down. I thought the
>problem was a loose connection inside the charger. I checked all
>connections and then tried another 300 watt MSW inverter. The first one now
>thinks that either the battery is too low or it is overloaded. It almost
>works. The second one shorted out and blew the fuse. It may be possible to
>repair but it'll have to wait. Most recently my 800 watt Vector SST
>inverter quit working while powering the two chargers. It is under
>warranty. It now says "OL" all the time. I can't really include the Wagan
>700 watt inverter in this scenerio because it was destroyed by overvoltage
>when I connected it to the alternator without a battery in parallel. I
>replaced 5 or 6 capacitors and it seemed ok until I used it briefly to power
>the battery chargers and then accidently ran a coffee maker with it which no
>doubt was a little bit too much for it.
>
>So, my question is can anyone tell me why a battery charger would cause the
>failure of so many inverters? I suspect the Schumacher charger to be the
>problem and will not use it on my next inverter but is it possible the
>Vector Smart Charger is causing the problem?
Hi,
I'd expect inverters are rated for a resistive load, for an inductive
load you need to look at VA and not watts. So a 200W charger probably
draws 300VA, ie the same current as a 300W resistive load.
Also a charger probably doesn't draw current evenly over the waveform,
but at the peaks instead. Since the heat in the in the transistors is
proportional to the _square_ of the current, any high current peaks
will create a lot more heat than a resistive load.
So a reasonable inverter for a 200W charger might be a 600W inverter
minimum.
There should be plenty of info on the web explaining the watts/VA
thing.
cheers,
Pete.
| |
| Vaughn 2005-12-17, 3:21 pm |
|
"Pete C" <petecnews@gmail.com> wrote in message
news:3bg8q1990nddp5ansam8ohe772chdfbtk3@4ax.com...
> On Fri, 16 Dec 2005 17:39:23 -0800, "Ulysses"
> <therealulysses@yahoo.com> wrote:
>
>
> I'd expect inverters are rated for a resistive load, for an inductive
> load you need to look at VA and not watts. So a 200W charger probably
> draws 300VA, ie the same current as a 300W resistive load.
Actually you gotta read the small print. If the device is rated in VA
rather than in watts, then you can assume that they are playing a numbers game
to inflate the numbers. For example: Consumer UPSs are almost always rated in
VA and they assume a horrible power factor. If you read the small print, you
find that your "800 VA" UPS is actually only good for 400 Watts!
Vaughn
| |
| Bruce in Alaska 2005-12-17, 5:21 pm |
| In article <11q6r2d39rvoi42@corp.supernews.com>,
"Ulysses" <therealulysses@yahoo.com> wrote:
> I have a problem.
snipped for brevity
>
> Please help.
>
> BTW I found a 1250 watt Inverter for only $50. Anyone ever heard of Homier
> aka HDC? They have few specs for it.
>
One thing you might look at is to rip out the diodes from your
alternator, measure the frequency, at load, and then wind a couple
of voltage upconversion transformer torriods to kick the voltage on the
long wire run up to 440 Vac or so and then use a duplicate one on the
other end to bring it back down to say around 13 Vac. Then rectify,
and filter it at the battery and feed that into your Three Stage Battery
Charger Input.
I got a neighbor that uses this system to power his place from a
MicroHydro that is 500 ft from the cabin, He only has the alternator
at the Damsite, and all the rest is in his Powerhouse, next to the cabin.
He pulls 1300 watts from the alternator and transforms that up to around
440Vac @ 2.7 amps for the run down from the dam. He gets about 1Kw into
the charging system for his 24Vdc Battery thru a MPPT controller that
does the Three State Charging. Works well for him untill the Stream
freezes over.
Bruce in alaska Westinghouse wan't a fool...you know......
--
add a <2> before @
| |
| Ulysses 2005-12-17, 10:21 pm |
|
"Pete C" <petecnews@gmail.com> wrote in message
news:3bg8q1990nddp5ansam8ohe772chdfbtk3@4ax.com...
> On Fri, 16 Dec 2005 17:39:23 -0800, "Ulysses"
> <therealulysses@yahoo.com> wrote:
>
eBay[color=darkred]
an[color=darkred]
ranging[color=darkred]
the[color=darkred]
now[color=darkred]
to[color=darkred]
Wagan[color=darkred]
overvoltage[color=darkred]
power[color=darkred]
no[color=darkred]
the[color=darkred]
>
> Hi,
>
> I'd expect inverters are rated for a resistive load, for an inductive
> load you need to look at VA and not watts. So a 200W charger probably
> draws 300VA, ie the same current as a 300W resistive load.
I was basing the power consumption on the current that the battery was
drawing X 14 volts. Even though the ammeter is telling me 15 amps it is
actually much higher because it is inductive?
>
> Also a charger probably doesn't draw current evenly over the waveform,
> but at the peaks instead. Since the heat in the in the transistors is
> proportional to the _square_ of the current, any high current peaks
> will create a lot more heat than a resistive load.
>
> So a reasonable inverter for a 200W charger might be a 600W inverter
> minimum.
I still suspect there is something about the Schumacher charger that is
screwing up my inverters. Unfortunately I don't have any left to try
running my other charger without the second one connected. From now on I
think I'll stick to using new inverters that are still under warranty ;-)
I'm also now thinking that the engine vibration might be a culprit too but
the smaller inverters (300 watt) were not subjected to the vibration but now
it sounds like they had a seperate, different reason for failure.
Anyone have an opinion on Vector Marine MSW inverters? They claim
resistance to vibration as well as moisture.
I'm not going to buy another Vector until I see what they do about the one I
sent back to them for warranty repair.
>
> There should be plenty of info on the web explaining the watts/VA
> thing.
>
> cheers,
> Pete.
| |
| meow2222@care2.com 2005-12-18, 12:21 pm |
| Ulysses wrote:
> I have a problem. I keep blowing up inverters. Then I find myself on eBay
> looking for more to buy. I am running a 63 Amp alternator with a 4 HP
> engine. It still has the built-in voltage regulator. It is connected to an
> 85 Ah deep cycle battery. I have had, so far, 4 different inverters ranging
> from 300-800 watts connected to it which I was using to power battery
> chargers mainly. One of the battery chargers is a Vector 40 amp Smart
> Charger. The other is a Schumacher 15 amp automatic charger that is no
> longer automatic. I thought it would be safe to power the 15 amp charger
> with a 300 watt MSW inverter as it usually draws less than 200 watts.
> Before it died the ammeter needle was bouncing up and down. I thought the
> problem was a loose connection inside the charger. I checked all
> connections and then tried another 300 watt MSW inverter. The first one now
> thinks that either the battery is too low or it is overloaded. It almost
> works. The second one shorted out and blew the fuse. It may be possible to
> repair but it'll have to wait. Most recently my 800 watt Vector SST
> inverter quit working while powering the two chargers. It is under
> warranty. It now says "OL" all the time. I can't really include the Wagan
> 700 watt inverter in this scenerio because it was destroyed by overvoltage
> when I connected it to the alternator without a battery in parallel. I
> replaced 5 or 6 capacitors and it seemed ok until I used it briefly to power
> the battery chargers and then accidently ran a coffee maker with it which no
> doubt was a little bit too much for it.
>
> So, my question is can anyone tell me why a battery charger would cause the
> failure of so many inverters? I suspect the Schumacher charger to be the
> problem and will not use it on my next inverter but is it possible the
> Vector Smart Charger is causing the problem?
>
> I need to charge two sets of batteries that are about 100 feet apart.
> Charging directly from the alternator will work fine for my main battery
> bank but I still need to charge the other one somehow. So far the built-in
> voltage regulator in the alternator keeps up with the inverters demand and
> keeps the deep cycle battery charged and apparently is not overcharging it.
> I have been looking at the different charge controller circuits so I can
> have the option of charging directly but I'm afraid the battery life will
> diminish without the regulated 3-stage charging I also like the option of
> using the setup as an AC generator but I'm tired of destroying inverters.
>
> Please help.
>
> BTW I found a 1250 watt Inverter for only $50. Anyone ever heard of Homier
> aka HDC? They have few specs for it.
>
> http://cgi.ebay.com/ws/eBayISAPI.dl...99174&ssPageNam
> e=STRK:MEWA:IT#ebayphotohosting
Youre not even beginning to take proper care of your invertors. If you
were my customer I'd offload you promptly.
Given this situation I'd suggest making a vibrating invertor. Theyre
easy to make and just about nothing can destroy them.
Meanwhile do the decent honest folk a favour, quit abusing their
invertors and claiming under warranty.
As for your 100' battery charging, I dont know why you dont just use a
reasonably chunky mains cable and leave it connected. It'll have all
day to charge at a lowish rate, and the cable is far less money than
your proposed solution.
NT
| |
| Vaughn 2005-12-18, 1:21 pm |
|
<meow2222@care2.com> wrote in message
news:1134920211.043633.227500@g14g2000cwa.googlegroups.com...
> Youre not even beginning to take proper care of your invertors. If you
> were my customer I'd offload you promptly.
Please explain to us what Ulysses is doing wrong. It is certainly not
clear to me.
>
> Given this situation I'd suggest making a vibrating invertor. Theyre
> easy to make and just about nothing can destroy them.
Please explain what a vibrating inverter is. I remember having an inverter
decades ago that used a transformer and a mechanical vibrator to chop the DC.
Is that what you are talking about?
>
> Meanwhile do the decent honest folk a favour, quit abusing their
> invertors and claiming under warranty.
Again, please explain how you think Ulysses is abusing his inverters. I
believe you are leaving both Ulysses and myself clueless here.
Vaughn
| |
| Pete C 2005-12-18, 2:21 pm |
| On Sat, 17 Dec 2005 17:43:03 -0800, "Ulysses"
<therealulysses@yahoo.com> wrote:
>
>"Pete C" <petecnews@gmail.com> wrote in message
>news:3bg8q1990nddp5ansam8ohe772chdfbtk3@4ax.com...
>
>I was basing the power consumption on the current that the battery was
>drawing X 14 volts. Even though the ammeter is telling me 15 amps it is
>actually much higher because it is inductive?
Not quite, that's the DC current from the battery, what's important is
the AC current from it's output.
This link explain a bit about resistive and inductive loads, it's
written with a generator in mind though it also applies to inverters.
<http://www.xantrex.com/web/id/735/docserve.asp>
Also see:
<http://groups.google.com/groups?q=1...=en&sa=N&tab=wg>
>
>I still suspect there is something about the Schumacher charger that is
>screwing up my inverters. Unfortunately I don't have any left to try
>running my other charger without the second one connected. From now on I
>think I'll stick to using new inverters that are still under warranty ;-)
Try asking the inverter makers about using them with an inductive
load. To play safe a 200W inductive load needs a 600W inverter unless
the inverter makers say otherwise.
[color=darkred]
>I'm also now thinking that the engine vibration might be a culprit too but
>the smaller inverters (300 watt) were not subjected to the vibration but now
>it sounds like they had a seperate, different reason for failure.
>
>Anyone have an opinion on Vector Marine MSW inverters? They claim
>resistance to vibration as well as moisture.
>
>I'm not going to buy another Vector until I see what they do about the one I
>sent back to them for warranty repair.
>
This is the bit you're missing.
cheers,
Pete.
| |
| Ulysses 2005-12-18, 10:21 pm |
|
"Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote in message
news:qZfpf.308288$zb5.121268@bgtnsc04-news.ops.worldnet.att.net...
>
> <meow2222@care2.com> wrote in message
> news:1134920211.043633.227500@g14g2000cwa.googlegroups.com...
>
>
> Please explain to us what Ulysses is doing wrong. It is certainly
not
> clear to me.
>
> Please explain what a vibrating inverter is. I remember having an
inverter
> decades ago that used a transformer and a mechanical vibrator to chop the
DC.
> Is that what you are talking about?
>
>
> Again, please explain how you think Ulysses is abusing his inverters.
I
> believe you are leaving both Ulysses and myself clueless here.
The first step to recovery is admiting you have a problem and I have done
that ;-)
I had an inverter in a '61 Volkswagen that was used to power the radio
(superdeluxe Bug--even had a sunroof!). It had vacuum tubes but I don't
recall if it vibrated. I probably would have noticed.
My grand delusion is to make an inverter generator using the 'ol
engine/alternator method. I have a Honda eu2000i and it powers the battery
chargers just fine. I want to make something more serviceable as Hondas can
be unrepairable due to the expense. My first eu2000 wore out and there are
no short blocks or replacement engines available so I want something I can
stick any old engine or alternator or inverter in. In the not-too-distant
future I will tear down the Honda and find out if another Honda engine can
be adapted to it but due to the alternator design I suspect the only choice
will be to rebuild the existing engine. I assume it is a GX engine and
they, as far as I know, do not have such things as replacable crankshaft
bearings etc. I still have the inverter and it still works but I cannot
find out how to wire it or what voltage is required.
>
> Vaughn
>
>
>
| |
| Vaughn 2005-12-18, 10:21 pm |
|
"Ulysses" <therealulysses@yahoo.com> wrote in message
news:11qc4bs1hk7avb0@corp.supernews.com...
>
> I had an inverter in a '61 Volkswagen that was used to power the radio
> (superdeluxe Bug--even had a sunroof!). It had vacuum tubes but I don't
> recall if it vibrated. I probably would have noticed.
Are you old enough to remember when car radios had vibrators? If the radio
was still quiet after a reasonable warm-up time, you laid your hand on the dash
to feel for the vibration. If you felt nothing, you rapped the dash smartly.
Often that would shock the vibrator into motion and the radio would suddenly
come to life. The vibrator was the most troublesome part of the radio, closely
followed by the tubes. The vibrator plugged in just like a tube, but replacing
it was not as easy as that. You were really supposed to replace a special
capacitor, (just like when you change the points in a car) and it was usually
soldered in underneath the chassis with the rest of the small bits.
{Back to the present}
Vaughn
| |
| meow2222@care2.com 2005-12-19, 12:21 am |
| Vaughn wrote:
> <meow2222@care2.com> wrote in message
> news:1134920211.043633.227500@g14g2000cwa.googlegroups.com...
>
>
> Please explain to us what Ulysses is doing wrong. It is certainly not
> clear to me.
ok, below
>
> Please explain what a vibrating inverter is. I remember having an inverter
> decades ago that used a transformer and a mechanical vibrator to chop the DC.
> Is that what you are talking about?
yes, just a relay set to self vibrate, driving an iron transformer.
Simple, basic, heavy, cheap, and almost indestructible. Will survive
all the abuses he's putting his invertors to.
>
> Again, please explain how you think Ulysses is abusing his inverters. I
> believe you are leaving both Ulysses and myself clueless here.
>
> Vaughn
OK. Ulysses wrote:
>I have had, so far, 4 different inverters ranging
>from 300-800 watts connected to it which I was using to power battery
>chargers mainly. One of the battery chargers is a Vector 40 amp Smart
>Charger.
40A @ 15v = 600 watts.
Allow 75% efficiency, and input power will be 600/.75 = 800 watts.
Now consider that whether these are electronic hf transformers, or
heavy iron transformers, either way most of this power is being
consumed on the crest of the mains waveform. This is especially true
with the more likely electronic transformer option, sine there is
little limitation to high side capacitor charging current.
So we can expect a crest current of many times 800/110, ie many times
7A. And this clown is running that on invertors rated 300-800w.
>I have a problem. I keep blowing up inverters. Then I find myself on eBay
>looking for more to buy.
He knows he's killing them, so he goes and gets more to do the same
with, still without solving the problem, without working out whats
wrong first.
>the Wagan 700 watt inverter
snip
>and then accidently ran a coffee maker with it which no
>doubt was a little bit too much for it.
So hes not taking sufficient care here at all. When working with
limited current supplies I write the current consumption on each plug,
and the max output on each socket.
>From now on I
>think I'll stick to using new inverters that are still under warranty ;-)
And plans to continue abusing them and simply claiming on warranties
repeatedly. Here this might possibly amount to obtaining (replacement)
goods by deception, which is a criminal offence. It certainly amounts
to a nightmare customer abusing his suppliers.
> I'm also now thinking that the engine vibration might be a culprit too but
more abuse
>I'm not going to buy another Vector until I see what they do about the one I
>sent back to them for warranty repair.
more abuse
I'm glad to see he's finally admitted his invertors are powerless, lets
hope he now starts to treat both his invertors and his suppliers
responsibly.
NT
| |
| Bob Adkins 2005-12-19, 1:21 pm |
| On Fri, 16 Dec 2005 20:07:07 -0800, "Ulysses" <therealulysses@yahoo.com>
wrote:
>
>Interesting idea. Sound kinda redundant but I'll think about it.
Charging a battery from a battery charger powered by an inverter powered by
a battery charger (alternator) is about as redundant as you can get. 
If I were you, I think I would concentrate on making the alternator charge
the batteries directly, as they are designed to do. I would try my best to
remove the AC charger from the loop.
--
Bob
| |
| Ulysses 2005-12-19, 8:21 pm |
|
"Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote in message
news:6Hopf.310878$zb5.63923@bgtnsc04-news.ops.worldnet.att.net...
>
> "Ulysses" <therealulysses@yahoo.com> wrote in message
> news:11qc4bs1hk7avb0@corp.supernews.com...
>
> Are you old enough to remember when car radios had vibrators?
I still have a couple of years to go before they bestow the honor of "senior
citizen" upon me. I guess that's not old enough because what you are saying
does not sound familiar.
OTOH I am old enough to have an oscilloscope that has vacuum tubes in it ;-)
If the radio
> was still quiet after a reasonable warm-up time, you laid your hand on the
dash
> to feel for the vibration. If you felt nothing, you rapped the dash
smartly.
> Often that would shock the vibrator into motion and the radio would
suddenly
> come to life. The vibrator was the most troublesome part of the radio,
closely
> followed by the tubes. The vibrator plugged in just like a tube, but
replacing
> it was not as easy as that. You were really supposed to replace a special
> capacitor, (just like when you change the points in a car) and it was
usually
> soldered in underneath the chassis with the rest of the small bits.
>
> {Back to the present}
> Vaughn
>
>
| |
| Ulysses 2005-12-19, 8:21 pm |
|
<meow2222@care2.com> wrote in message
news:1134965519.086147.187160@f14g2000cwb.googlegroups.com...
> Vaughn wrote:
not[color=darkred]
>
> ok, below
>
>
inverter[color=darkred]
the DC.[color=darkred]
>
> yes, just a relay set to self vibrate, driving an iron transformer.
> Simple, basic, heavy, cheap, and almost indestructible. Will survive
> all the abuses he's putting his invertors to.
I only have a general idea of what you are talking about here. I will
attempt to find more info online but if you have any links I would
appreciate them.
>
>
inverters. I[color=darkred]
>
>
> OK. Ulysses wrote:
>
>
> 40A @ 15v = 600 watts.
> Allow 75% efficiency, and input power will be 600/.75 = 800 watts.
> Now consider that whether these are electronic hf transformers, or
> heavy iron transformers, either way most of this power is being
> consumed on the crest of the mains waveform. This is especially true
> with the more likely electronic transformer option, sine there is
> little limitation to high side capacitor charging current.
>
> So we can expect a crest current of many times 800/110, ie many times
> 7A. And this clown is running that on invertors rated 300-800w.
I resemble that comment!
>
>
eBay[color=darkred]
>
> He knows he's killing them, so he goes and gets more to do the same
> with, still without solving the problem, without working out whats
> wrong first.
>
>
> snip
>
> So hes not taking sufficient care here at all. When working with
> limited current supplies I write the current consumption on each plug,
> and the max output on each socket.
>
>
>
> And plans to continue abusing them and simply claiming on warranties
> repeatedly. Here this might possibly amount to obtaining (replacement)
> goods by deception, which is a criminal offence. It certainly amounts
> to a nightmare customer abusing his suppliers.
>
>
but[color=darkred]
>
> more abuse
>
>
one I[color=darkred]
>
> more abuse
>
>
> I'm glad to see he's finally admitted his invertors are powerless, lets
> hope he now starts to treat both his invertors and his suppliers
> responsibly.
>
>
> NT
>
| |
| Vaughn 2005-12-19, 10:21 pm |
|
"Ulysses" <therealulysses@yahoo.com> wrote in message
news:11qeiju1csf2365@corp.supernews.com...
>
> I only have a general idea of what you are talking about here. I will
> attempt to find more info online but if you have any links I would
> appreciate them.
I know how to make that work, but I am not even a little optimistic about
that approach. He is talking about a mechanical contact opening and closing
(more or less) sixty times per second while switching several amps into an
inductive circuit. How long do you think that would last? I am an old traffic
signal guy who cut his teeth on mechanical relays. I respectfully believe that
I have a pretty good idea of their advantages and limitations. I gave up on
them (99%) decades ago. We have better things now.
Vaughn
| |
| Ulysses 2005-12-19, 10:21 pm |
|
<meow2222@care2.com> wrote in message
news:1134965519.086147.187160@f14g2000cwb.googlegroups.com...
> Vaughn wrote:
not[color=darkred]
>
> ok, below
>
>
inverter[color=darkred]
the DC.[color=darkred]
>
> yes, just a relay set to self vibrate, driving an iron transformer.
> Simple, basic, heavy, cheap, and almost indestructible. Will survive
> all the abuses he's putting his invertors to.
Ok, so you are talking about pulsing a DC current through a transformer and
getting some psuedo AC? How do you control both the frequency and the
voltage? Just pick a winding? Won't this amount to half-wave AC? And a
very squqare half-wave? From what you (or somebody) said it sounds like
battery chargers would not like that very much. What is the trick?
>
>
inverters. I[color=darkred]
>
>
> OK. Ulysses wrote:
>
>
> 40A @ 15v = 600 watts.
> Allow 75% efficiency, and input power will be 600/.75 = 800 watts.
> Now consider that whether these are electronic hf transformers, or
> heavy iron transformers, either way most of this power is being
> consumed on the crest of the mains waveform. This is especially true
> with the more likely electronic transformer option, sine there is
> little limitation to high side capacitor charging current.
>
> So we can expect a crest current of many times 800/110, ie many times
> 7A. And this clown is running that on invertors rated 300-800w.
>
>
eBay[color=darkred]
>
> He knows he's killing them, so he goes and gets more to do the same
> with, still without solving the problem, without working out whats
> wrong first.
>
>
> snip
>
> So hes not taking sufficient care here at all. When working with
> limited current supplies I write the current consumption on each plug,
> and the max output on each socket.
>
>
>
> And plans to continue abusing them and simply claiming on warranties
> repeatedly. Here this might possibly amount to obtaining (replacement)
> goods by deception, which is a criminal offence. It certainly amounts
> to a nightmare customer abusing his suppliers.
I did not realize that I was abusing them for the most part. They say they
will operate induction load but they do not explain in the instructions how
to calculate those particular loads. They do explain how to calculate
resistive loads however. In my ignorance I did not know that a 200 watt
resistive load is not the same as a 200 watt inductive load. I thought only
the startup load was higher. That's why I'm asking what I'm doing wrong.
>
>
but[color=darkred]
>
> more abuse
>
>
one I[color=darkred]
>
> more abuse
>
>
> I'm glad to see he's finally admitted his invertors are powerless, lets
> hope he now starts to treat both his invertors and his suppliers
> responsibly.
>
>
> NT
>
| |
| Ulysses 2005-12-19, 11:21 pm |
|
"Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote in message
news:M9Jpf.316814$zb5.93231@bgtnsc04-news.ops.worldnet.att.net...
>
> "Ulysses" <therealulysses@yahoo.com> wrote in message
> news:11qeiju1csf2365@corp.supernews.com...
>
> I know how to make that work, but I am not even a little optimistic
about
> that approach. He is talking about a mechanical contact opening and
closing
> (more or less) sixty times per second while switching several amps into an
> inductive circuit. How long do you think that would last? I am an old
traffic
> signal guy who cut his teeth on mechanical relays. I respectfully believe
that
> I have a pretty good idea of their advantages and limitations. I gave up
on
> them (99%) decades ago. We have better things now.
>
> Vaughn
>
>
If I wanted to pulse DC I think I'd go with a 555 timer IC controlling a
power transistor.
At least you mentioned the 60 times a second. I was wondering how it would
be possible to control both the output voltage and the frequency plus you
would, I think, end up with a half square wave which seems like it would not
be very useful for powering a battery charger. Does a half wave device even
qualify for the definition of "inverter?" I always thought that meant that
the wave was formed, inverted, formed again....
Just out of curiousity is the so-called "modified sine wave" produced by
somehow producing a smaller, shorter square wave at the peak of another
square wave?
| |
| meow2222@care2.com 2005-12-20, 12:21 am |
| Vaughn wrote:
> "Ulysses" <therealulysses@yahoo.com> wrote in message
> news:11qeiju1csf2365@corp.supernews.com...
>
> I know how to make that work, but I am not even a little optimistic about
> that approach. He is talking about a mechanical contact opening and closing
> (more or less) sixty times per second while switching several amps into an
> inductive circuit. How long do you think that would last? I am an old traffic
> signal guy who cut his teeth on mechanical relays. I respectfully believe that
> I have a pretty good idea of their advantages and limitations. I gave up on
> them (99%) decades ago. We have better things now.
>
> Vaughn
They were standard kit in the 1940s, and suffer from around 2% failure
rate. This is why they were replaced with newer technology. Theyre also
large and heavy, since they operate at 50/60Hz, and this is not ideal
for mobile military use. Contact arcing is handled by snubbers and
physically large contacts. This is all well established technology.
The advantage is theyre abuse proof. Ulysses is killing invertor after
invertor: surely a 2% failure rate would be a huge improvement on that.
The other advantage is that he could make something a _lot_ more
powerful without spending any more than for a 300w invertor. A rewound
microwave oven transformer would get you about 1kW out, 2 you could
cook on all day long.
PS re contact failures, with a home made open structure any failure is
elementary to fix, all you need is a miniature file to dress the
contacts.
NT
| |
| meow2222@care2.com 2005-12-20, 1:21 am |
| > If I wanted to pulse DC I think I'd go with a 555 timer IC controlling a
> power transistor.
If you want something that will die just like your other invertors,
this would be ideal.
> At least you mentioned the 60 times a second. I was wondering how it would
> be possible to control both the output voltage and the frequency
Frequency is controlled by mechanical resonance.
V_out is controlled:
a) roughly by the winding ratio of the transformer
b) more accurately by a switch selecting a tapping
c) automatically if you wish by a relay switching the tapping
> plus you
> would, I think, end up with a half square wave
no, you get msw.
NT
| |
|
| In article <M9Jpf.316814$zb5.93231@bgtnsc04-news.ops.worldnet.att.net>,
"Vaughn" <vaughnsimonHATESSPAM@att.fake.net> wrote:
> "Ulysses" <therealulysses@yahoo.com> wrote in message
> news:11qeiju1csf2365@corp.supernews.com...
>
> I know how to make that work, but I am not even a little optimistic about
> that approach. He is talking about a mechanical contact opening and closing
> (more or less) sixty times per second while switching several amps into an
> inductive circuit. How long do you think that would last? I am an old
> traffic
> signal guy who cut his teeth on mechanical relays. I respectfully believe
> that
> I have a pretty good idea of their advantages and limitations. I gave up on
> them (99%) decades ago. We have better things now.
>
> Vaughn
>
>
You can do the same thing with a couple of Power MosFet's driving a
centertapped transformer winding and use a cmos clockchip to supply the
60Hz timebase......the above is called "An Inverter"....... Some of us
"Really Old Farts" can remember the pre-solidstate vibrators used in
mobile equipment. Hell, Motorola had them in all the old 30D 50's
Police Radios.
Me
| |
|
|
| SolarFlare 2005-12-20, 8:21 pm |
| If you can get that DC compenent to pass through a
transformer you are in for some big money in your life,
because nobody else can.
"Ulysses" <therealulysses@yahoo.com> wrote in message
news:11qeob6n8cjl4b1@corp.supernews.com...
> Ok, so you are talking about pulsing a DC current
through a transformer and
> getting some psuedo AC? How do you control both the
frequency and the
> voltage? Just pick a winding? Won't this amount to
half-wave AC? And a
> very squqare half-wave? From what you (or somebody)
said it sounds like
> battery chargers would not like that very much. What
is the trick?
| |
| Ulysses 2005-12-21, 4:21 pm |
|
"SolarFlare" <sfl.are@hot.mail.invalid> wrote in message
news:Pf6dnf8IFPM6ATXeRVn-jw@golden.net...
> If you can get that DC compenent to pass through a
> transformer you are in for some big money in your life,
> because nobody else can.
I'm not sure what you mean. If you pulse DC you can (or at least I can) get
it through a transformer. I made a gizmo that used a timer circuit to pulse
a "C" battery via a relay through a transformer and it measured around 45
VAC with an analog meter. I did not put it on a scope because I just
assumed it would be a half-square wave (maybe more like a shark fin). Meow
said it would be MSW but I think he was talking about the output from a
motor generator which, from what I understand, is basically an alternator so
I would expect something close to a sine wave. From what some have said in
this thread I should be using a belt-driven 120 VAC alternator unstead of a
car alternator. If I could find one in the 2000 watt range for not too much
$$$ I might be able to gear down the engine enough to run the engine at a
reduced speed such as I'm doing now with my car alternator setup. Right now
I can charge my battery bank at about 25 amps with the engine running barely
above idle except it sounds like it's struggling at that speed so I speed it
up until it sounds OK.
If anyone has more info on how I can build an indestructable inverter such
as Meow suggested I would appreciate it.
>
> "Ulysses" <therealulysses@yahoo.com> wrote in message
> news:11qeob6n8cjl4b1@corp.supernews.com...
> through a transformer and
> frequency and the
> half-wave AC? And a
> said it sounds like
> is the trick?
>
>
| |
| SolarFlare 2005-12-21, 11:21 pm |
| You even stated yourself, you measured the other side
with an **AC** voltmeter.
A transformer will lose the DC component of the
waveform. When you attached the positive lead the
output went positive and ramped right back down to
zero. Now when you remove the positive lead the signal
goes to zero or negative in direction and again the
output of the transformer will go negative and then
ramp back to zero.
Only changes of state get transformed. If they are
faster than the output can decline it looks like the
same wave. No matter what static voltage you put on the
one winding of a transforer the other windings will put
out zero volts.
"Ulysses" <therealulysses@yahoo.com> wrote in message
news:11qjcqo74beaja6@corp.supernews.com...
>
> "SolarFlare" <sfl.are@hot.mail.invalid> wrote in
message
> news:Pf6dnf8IFPM6ATXeRVn-jw@golden.net...
life,[color=darkred]
>
> I'm not sure what you mean. If you pulse DC you can
(or at least I can) get
> it through a transformer. I made a gizmo that used a
timer circuit to pulse
> a "C" battery via a relay through a transformer and
it measured around 45
> VAC with an analog meter. I did not put it on a
scope because I just
> assumed it would be a half-square wave (maybe more
like a shark fin). Meow
> said it would be MSW but I think he was talking about
the output from a
> motor generator which, from what I understand, is
basically an alternator so
> I would expect something close to a sine wave. From
what some have said in
> this thread I should be using a belt-driven 120 VAC
alternator unstead of a
> car alternator. If I could find one in the 2000 watt
range for not too much
> $$$ I might be able to gear down the engine enough to
run the engine at a
> reduced speed such as I'm doing now with my car
alternator setup. Right now
> I can charge my battery bank at about 25 amps with
the engine running barely
> above idle except it sounds like it's struggling at
that speed so I speed it
> up until it sounds OK.
>
> If anyone has more info on how I can build an
indestructable inverter such
> as Meow suggested I would appreciate it.
>
message[color=darkred]
the[color=darkred]
to[color=darkred]
somebody)[color=darkred]
What[color=darkred]
>
>
| |
| meow2222@care2.com 2005-12-22, 3:21 am |
| Ulysses wrote:
> <meow2222@care2.com> wrote in message
Looks like what I wrote vanished...
>
> Ok, so you are talking about pulsing a DC current through a transformer
yes
> and
> getting some psuedo AC?
real ac
> How do you control both the frequency
mechanical resonance of the vibrator
> and the
> voltage? Just pick a winding?
as before, let the relay switch tappings to tweek the V_out
> Won't this amount to half-wave AC? And a
> very squqare half-wave?
no, you get msw
> From what you (or somebody) said it sounds like
> battery chargers would not like that very much.
theyll like it fine, whether theyre modern electronic ones or older
transformer types.
> What is the trick?
trick ?
> I did not realize that I was abusing them for the most part. They say they
> will operate induction load but they do not explain in the instructions how
> to calculate those particular loads. They do explain how to calculate
> resistive loads however. In my ignorance I did not know that a 200 watt
> resistive load is not the same as a 200 watt inductive load. I thought only
> the startup load was higher. That's why I'm asking what I'm doing wrong.
You need to calculate the current draw of your loads, and not overload
the invertors. Your loads are a large number times too heavy.
Also I doubt your cheapie invertors were designed for rugged service,
so engine vibration is a no-no.
NT
| |
| meow2222@care2.com 2005-12-22, 3:21 am |
| Ulysses wrote:
> "SolarFlare" <sfl.are@hot.mail.invalid> wrote in message
> news:Pf6dnf8IFPM6ATXeRVn-jw@golden.net...
Ahh... its done in spot welders, where the output transformer is fed on
dc. Admittedly they will only transform dc for a very short amount of
time
In impracitcal principle, if you wanted continuous dc you could have
say 3 transformers, each fed with chopped dc in, each giving chopped dc
out, and you could combine the outputs to get dc. It would be
stretching the boundaries to call it transforming dc, but there's
always tricks to get the seemingly undoable.
[color=darkred]
> assumed it would be a half-square wave (maybe more like a shark fin). Meow
> said it would be MSW but I think he was talking about the output from a
> motor generator which,
no, those work but are seriously inefficient. Expect 65%.
> If anyone has more info on how I can build an indestructable inverter such
> as Meow suggested I would appreciate it.
There are 2 parts to it, a big transformer, and a vibrator.
The vibrator is a large relay with 2 way contacts. You can either use a
big 50A relay, or make something yourself out of clockspring steel
strip etc. The supply to the relay coil goes thru its normally closed
contacts. On applying power, the coil energises, relay opens, cutting
off its coil power, so it closes again... repeat ad infinitum. A
homemade relay would use a long springy armature, giving mechanical
resnoance and thus much better frequency control. But a commercial plug
in relay will work.
Add good snubbing to the contacts, this will be needed. Thats means
large value CR across each.
Now, your 12v supply is chopped by the relay into 2 streams, one at
each contact, each switching on and off alternately.
The transformer uses a centre tapped secondary winding, and we feed
power into that from the relay. So one half of the cycle the left end
gets power, the other half the right end gets power. And half the time
neither does, as the relay contact strip is between the 2 contacts.
The transformer centre tap goes to 0v. This means the transfoerm sees
ac, no dc component. In practice its wise to tweak the mechanics of the
relay a bit to ensure symmetrical drive, as any assymetry will cause
power waste and transformer heating.
Build that then we can add voltage regulation. You reg v by
automatiaclly switching between output v taps using a 2nd relay with a
zener/diac/etc.
NT
| |
| Ulysses 2005-12-22, 5:21 pm |
| I'm not trying to argue with you I just didn't understand that you meant it
had to be DC at the output of the transformer.
"SolarFlare" <sfl.are@hot.mail.invalid> wrote in message
news:eJidnaSX967yjzfenZ2dnUVZ_tOdnZ2d@golden.net...
> You even stated yourself, you measured the other side
> with an **AC** voltmeter.
>
> A transformer will lose the DC component of the
> waveform. When you attached the positive lead the
> output went positive and ramped right back down to
> zero. Now when you remove the positive lead the signal
> goes to zero or negative in direction and again the
> output of the transformer will go negative and then
> ramp back to zero.
>
> Only changes of state get transformed. If they are
> faster than the output can decline it looks like the
> same wave. No matter what static voltage you put on the
> one winding of a transforer the other windings will put
> out zero volts.
>
>
> "Ulysses" <therealulysses@yahoo.com> wrote in message
> news:11qjcqo74beaja6@corp.supernews.com...
> message
> life,
> (or at least I can) get
> timer circuit to pulse
> it measured around 45
> scope because I just
> like a shark fin). Meow
> the output from a
> basically an alternator so
> what some have said in
> alternator unstead of a
> range for not too much
> run the engine at a
> alternator setup. Right now
> the engine running barely
> that speed so I speed it
> indestructable inverter such
> message
> the
> to
> somebody)
> What
>
>
| |
| Ulysses 2005-12-22, 5:21 pm |
|
<meow2222@care2.com> wrote in message
news:1135234895.917915.138130@g49g2000cwa.googlegroups.com...
> Ulysses wrote:
>
>
> Ahh... its done in spot welders, where the output transformer is fed on
> dc. Admittedly they will only transform dc for a very short amount of
> time
>
> In impracitcal principle, if you wanted continuous dc you could have
> say 3 transformers, each fed with chopped dc in, each giving chopped dc
> out, and you could combine the outputs to get dc. It would be
> stretching the boundaries to call it transforming dc, but there's
> always tricks to get the seemingly undoable.
>
>
Meow[color=darkred]
>
> no, those work but are seriously inefficient. Expect 65%.
>
>
such[color=darkred]
>
> There are 2 parts to it, a big transformer, and a vibrator.
>
> The vibrator is a large relay with 2 way contacts. You can either use a
> big 50A relay, or make something yourself out of clockspring steel
> strip etc. The supply to the relay coil goes thru its normally closed
> contacts. On applying power, the coil energises, relay opens, cutting
> off its coil power, so it closes again... repeat ad infinitum. A
> homemade relay would use a long springy armature, giving mechanical
> resnoance and thus much better frequency control. But a commercial plug
> in relay will work.
>
> Add good snubbing to the contacts, this will be needed. Thats means
> large value CR across each.
>
> Now, your 12v supply is chopped by the relay into 2 streams, one at
> each contact, each switching on and off alternately.
>
>
> The transformer uses a centre tapped secondary winding, and we feed
> power into that from the relay. So one half of the cycle the left end
> gets power, the other half the right end gets power. And half the time
> neither does, as the relay contact strip is between the 2 contacts.
>
> The transformer centre tap goes to 0v. This means the transfoerm sees
> ac, no dc component. In practice its wise to tweak the mechanics of the
> relay a bit to ensure symmetrical drive, as any assymetry will cause
> power waste and transformer heating.
>
> Build that then we can add voltage regulation. You reg v by
> automatiaclly switching between output v taps using a 2nd relay with a
> zener/diac/etc.
>
>
> NT
>
Thanks for the great info. I understand most of it except the voltage
regulation. Is that similar to the old regulators on cars that used an
adjustable relay? And I'm trying to figure out what CR means for snubbing
:-|
| |
| billmcf 2005-12-22, 8:21 pm |
| I've successfully operated a Vector 40A smart charger from a MSW
inverter for several hours at a time, but in my case the inverter was
rated at 1500 VA. The charger produced the full 40 amps, even though
the inverter's peak output voltage was low (145 V vs. 170 V from a wall
outlet). It also produced full output when powered by a generator.
That's not always the case with old-style transformer-diode chargers.
BTW, I looked at the Vector charger's input characteristics with a
Kill-a-Watt meter. It was about what I'd expect from a capacitor-input
switching power supply. If I recall correctly, the power factor was in
the neighborhood of 0.7. Efficiency was in the low 80% range.
P.S.: Don't use a Kill-a-Watt with a MSW inverter. The harmonics will
kill the Kill-a-Watt.
| |
| Steve Spence 2005-12-22, 10:21 pm |
| billmcf wrote:
> P.S.: Don't use a Kill-a-Watt with a MSW inverter. The harmonics will
> kill the Kill-a-Watt.
>
Not true. I've been using my KAW with my AC DELCO 2500 watt MSW inverter
for well over a year with no issues. Must depend on the quality of the
MSW inverter?
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
| |
| SolarFlare 2005-12-22, 11:21 pm |
| I have no idea where that idea came from. I doubt I
posted it.
"Ulysses" <therealulysses@yahoo.com> wrote in message
news:11qm4n5kcos5m16@corp.supernews.com...
> I'm not trying to argue with you I just didn't
understand that you meant it
> had to be DC at the output of the transformer.
>
> "SolarFlare" <sfl.are@hot.mail.invalid> wrote in
message
> news:eJidnaSX967yjzfenZ2dnUVZ_tOdnZ2d@golden.net...
side[color=darkred]
signal[color=darkred]
the[color=darkred]
the[color=darkred]
put[color=darkred]
message[color=darkred]
through a[color=darkred]
your[color=darkred]
can[color=darkred]
used a[color=darkred]
and[color=darkred]
more[color=darkred]
about[color=darkred]
From[color=darkred]
VAC[color=darkred]
watt[color=darkred]
enough to[color=darkred]
with[color=darkred]
at[color=darkred]
current[color=darkred]
both[color=darkred]
amount[color=darkred]
much.[color=darkred]
>
>
| |
| SolarFlare 2005-12-22, 11:21 pm |
| M)ostly
S)quare
W)ave
?
"Steve Spence" <sspence@green-trust.org> wrote in
message news:43ab5183$1_1@newsfeed.slurp.net...
> billmcf wrote:
>
The harmonics will[color=darkred]
>
> Not true. I've been using my KAW with my AC DELCO
2500 watt MSW inverter
> for well over a year with no issues. Must depend on
the quality of the
> MSW inverter?
>
>
> --
> Steve Spence
> Dir., Green Trust, http://www.green-trust.org
> Contributing Editor, http://www.off-grid.net
> http://www.rebelwolf.com/essn.html
| |
| meow2222@care2.com 2005-12-24, 5:21 am |
| Ulysses wrote:
> Thanks for the great info. I understand most of it except the voltage
> regulation. Is that similar to the old regulators on cars that used an
> adjustable relay?
Quite different principle. Get one working then you can add regulation.
Just add tappings on the mains wind side with -10%, +10%, +20%, so you
can select the best V_out, and later automate it.
> And I'm trying to figure out what CR means for snubbing
capacitor resistor
NT
| |
| billmcf 2005-12-29, 9:21 pm |
| The Kill-a-Watt uses an RC power supply, which is not very tolerant of
harmonics. Maybe Steve's inverter has some filtering. Mine killed the
Kill-a-Watt in less than a day.
| |
| Steve Spence 2005-12-29, 11:21 pm |
| billmcf wrote:
> The Kill-a-Watt uses an RC power supply, which is not very tolerant of
> harmonics. Maybe Steve's inverter has some filtering. Mine killed the
> Kill-a-Watt in less than a day.
>
It's a AC DELCO 2500 watt from BJ's Wholesale. $269
--
Steve Spence
Dir., Green Trust, http://www.green-trust.org
Contributing Editor, http://www.off-grid.net
http://www.rebelwolf.com/essn.html
|
|
|
|
|