|
Home > Archive > Electrical Engineering > July 2007 > Power Cost Meter for 115V?
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 |
Power Cost Meter for 115V?
|
|
|
| Can anyone recommend a simple power meter for a 115V 20A outlet that not
only measures amperage, but also has some ability to do power cost
calculations, based on a tariff rate you enter into it?
La Crosse Technology had a device named the Cost Control that did this, but
apparently they no longer make it.
--
Will
| |
|
| In article <saCdnZXKofbmJwfbnZ2dnUVZ_jCdnZ2d@giganews.com>, westes-
usc@noemail.nospam says...
> Can anyone recommend a simple power meter for a 115V 20A outlet that not
> only measures amperage, but also has some ability to do power cost
> calculations, based on a tariff rate you enter into it?
>
> La Crosse Technology had a device named the Cost Control that did this, but
> apparently they no longer make it.
>
Kill-A-Watt or Seasonic PowerAngel will measure power and energy
usage (PF, voltage, current, frequency, and anything else they could
think of ;). The Kill-A-Watt says it'll calculate and forecast
"cost". Either will do any measurements you need. You can get the
cost from there with a little arithmetic.
I paid $30 for the PowerAngel at NewEgg but I see Kill-A-Watts for
less than $25 on Amazon.
--
Keith
| |
|
| "krw" <krw@att.bizzzz> wrote in message
news:MPG.2104a4f2da965c6598a791@news.individual.net...
> In article <saCdnZXKofbmJwfbnZ2dnUVZ_jCdnZ2d@giganews.com>, westes-
> usc@noemail.nospam says...
> Kill-A-Watt or Seasonic PowerAngel will measure power and energy
> usage (PF, voltage, current, frequency, and anything else they could
> think of ;). The Kill-A-Watt says it'll calculate and forecast
> "cost". Either will do any measurements you need. You can get the
> cost from there with a little arithmetic.
>
> I paid $30 for the PowerAngel at NewEgg but I see Kill-A-Watts for
> less than $25 on Amazon.
Don't those devices make spot measurements? The nice thing about the La
Crosse was that it not only calculated the spot cost of energy, but
accumulated data over time and took average readings. So you could set it
to the cost per month, and periodically walk by and see the cost was $23 /
month, for example.
I need to install about 20 of these, and I wouldn't really look forward to
walking around and doing lots of spot measurements and then making my own
calculations. If you have multiple computers attached to one monitor, and
each of those has idle and loaded energy utilizations, it becomes nearly
impossible to correctly calculate the cost of energy consumption as more
than a possible range, since you don't know what percentage of time the
computer is in idle versus loaded states.
--
Will
| |
|
| In article <u5edna9WMJu-bQfbnZ2dnUVZ_remnZ2d@giganews.com>, westes-
usc@noemail.nospam says...
> "krw" <krw@att.bizzzz> wrote in message
> news:MPG.2104a4f2da965c6598a791@news.individual.net...
>
> Don't those devices make spot measurements? The nice thing about the La
> Crosse was that it not only calculated the spot cost of energy, but
> accumulated data over time and took average readings. So you could set it
> to the cost per month, and periodically walk by and see the cost was $23 /
> month, for example.
The PowerAngel measures kWh and Hours and I think the Kill-A-Watt is
the same (never used one). You'd have to divide to get the average
load.
> I need to install about 20 of these, and I wouldn't really look forward to
> walking around and doing lots of spot measurements and then making my own
> calculations. If you have multiple computers attached to one monitor, and
> each of those has idle and loaded energy utilizations, it becomes nearly
> impossible to correctly calculate the cost of energy consumption as more
> than a possible range, since you don't know what percentage of time the
> computer is in idle versus loaded states.
Since they do measure kWh (and h), it doesn't sound too hard to
figure out the real power usage. Peaks would be pretty simple to
measure also, to get a maximum (all computers going full tilt).
Keepitn track of twenty devices sounds like a lot of work anyway. A
spread sheet would make quick work of any calculations you need.
--
Keith
| |
| Eric9822 2007-07-17, 8:25 pm |
| On Jul 15, 9:12 pm, "Will" <westes-...@noemail.nospam> wrote:
> "krw" <k...@att.bizzzz> wrote in message
>
> news:MPG.2104a4f2da965c6598a791@news.individual.net...
>
>
>
>
>
>
>
>
>
> Don't those devices make spot measurements? The nice thing about the La
> Crosse was that it not only calculated the spot cost of energy, but
> accumulated data over time and took average readings. So you could set it
> to the cost per month, and periodically walk by and see the cost was $23 /
> month, for example.
>
> I need to install about 20 of these, and I wouldn't really look forward to
> walking around and doing lots of spot measurements and then making my own
> calculations. If you have multiple computers attached to one monitor, and
> each of those has idle and loaded energy utilizations, it becomes nearly
> impossible to correctly calculate the cost of energy consumption as more
> than a possible range, since you don't know what percentage of time the
> computer is in idle versus loaded states.
>
> --
> Will- Hide quoted text -
>
> - Show quoted text -
The Kill A Watt collects and accumulates data as well as tracks time
for as long as the unit is plugged in. Just make sure you get the KW
used and the elapsed time before unplugging it, there is no memory
retention. Works very well for something that only costs $25.00.
| |
|
| "Eric9822" <tisabooks@hotmail.com> wrote in message
news:1184715229.018365.247690@x35g2000prf.googlegroups.com...
> On Jul 15, 9:12 pm, "Will" <westes-...@noemail.nospam> wrote:
>
> The Kill A Watt collects and accumulates data as well as tracks time
> for as long as the unit is plugged in. Just make sure you get the KW
> used and the elapsed time before unplugging it, there is no memory
> retention. Works very well for something that only costs $25.00.
I would be willing to spend up to $100 per meter if there are any options.
--
Will
| |
|
| In article <UcKdndyTOMWIywDbnZ2dnUVZ_g2dnZ2d@giganews.com>, westes-
usc@noemail.nospam says...
> "Eric9822" <tisabooks@hotmail.com> wrote in message
> news:1184715229.018365.247690@x35g2000prf.googlegroups.com...
>
> I would be willing to spend up to $100 per meter if there are any options.
>
A quick web search turns up all sorts of power meters. Here is one
that records and has a USB interface (sounds like you could use it)
for $150:
http://www.powermeterstore.com/inde...roducts_id=1206
--
Keith
| |
| reqluq 2007-07-22, 1:25 pm |
| I had inquired about something like this a while back.. I have sub-let some
rooms and would like to know the actual power usage of each unit to charge
accordingly. It was suggested that I buy some second-hand refurbished meters
but I thought they were a bit too bulky. Would the total home energy
monitor kit do this effectively?
tia
req
"Will" <westes-usc@noemail.nospam> wrote in message
news:saCdnZXKofbmJwfbnZ2dnUVZ_jCdnZ2d@giganews.com...
> Can anyone recommend a simple power meter for a 115V 20A outlet that not
> only measures amperage, but also has some ability to do power cost
> calculations, based on a tariff rate you enter into it?
>
> La Crosse Technology had a device named the Cost Control that did this,
> but
> apparently they no longer make it.
>
> --
> Will
>
>
| |
| Palindrome 2007-07-22, 5:25 pm |
| reqluq wrote:
> I had inquired about something like this a while back.. I have sub-let some
> rooms and would like to know the actual power usage of each unit to charge
> accordingly. It was suggested that I buy some second-hand refurbished meters
> but I thought they were a bit too bulky. Would the total home energy
> monitor kit do this effectively?
The refurbished meters are going to be reliable and reasonably accurate.
Plus they don't lose their readings during power fails..
--
Sue
| |
| reqluq 2007-07-22, 5:25 pm |
| "Palindrome" <me9@privacy.net> wrote in message
news:yjNoi.211631$G_4.52510@fe09.news.easynews.com...
> reqluq wrote:
>
> The refurbished meters are going to be reliable and reasonably accurate.
> Plus they don't lose their readings during power fails..
> --
> Sue
Yes but I was hoping with all the advances in tech. that there would be a
better solution. It should not take more than a small onboard batt to keep
figures in memory if power goes.
req
| |
|
| "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
news:13a7gg7k0efuhe0@corp.supernews.com...
> "Palindrome" <me9@privacy.net> wrote in message
> news:yjNoi.211631$G_4.52510@fe09.news.easynews.com...
to[color=darkred]
>
> Yes but I was hoping with all the advances in tech. that there would be a
> better solution. It should not take more than a small onboard batt to keep
> figures in memory if power goes.
The problem with the power meter market is that it is really focused on
commercial multi-tenant billing solutions, and the meters are just
expensive, typically $400 to $900 each if you want something that you can
link to a computer by RS-485 or ethernet. Typically such installations are
done one meter per circuit, so if your tenants are each on different
circuits, now you are looking at multiple meters. It's hard to get a
payback on the investment.
The best commercial solution I found was from Satec, and they have an
ingenious product lets you put multiple current readers around specific
circuits, and feed the measurements all to a single device that reads up to
about nine circuits. This collector is then uplinked by RS-485 to
ethernet, and to software on your PC. It's under $1K, and at least it's
flexible to reorganize the groups of circuits you bill for, and consolidates
data collection to one place. The software doesn't look beautiful to be
sure, but I don't find many competitors either.
The open part of the market is the consumer who wants to measure and manage
energy utilization on 10 circuits in order to cut a $500 monthly bill to
$400. It's hard to justify spending $400 * 10 in dedicated monitors on
your fuse panel. It's barely acceptable to spend $1K for the Satec
solution. What would make a lot more sense to me would be some kind of
meter like the Kill-a-watt that has a wireless uplink to a central computer.
But price point for that thing would need to be around $100 / meter,
otherwise you don't pay back the investment fast enough to make it worth
doing out of pocket. I wasn't able to find this product. Everything I
could find was $400+ per meter.
--
Will
| |
| reqluq 2007-07-23, 3:25 am |
| "Will" <westes-usc@noemail.nospam> wrote in message
news:8KudnSuagPm4Tj7bnZ2dnUVZ_tWtnZ2d@giganews.com...
> "reqluq" <scredcropshonnospam@hotmail.com> wrote in message
> news:13a7gg7k0efuhe0@corp.supernews.com...
> to
>
> The problem with the power meter market is that it is really focused on
> commercial multi-tenant billing solutions, and the meters are just
> expensive, typically $400 to $900 each if you want something that you can
> link to a computer by RS-485 or ethernet. Typically such installations
> are
> done one meter per circuit, so if your tenants are each on different
> circuits, now you are looking at multiple meters. It's hard to get a
> payback on the investment.
>
> The best commercial solution I found was from Satec, and they have an
> ingenious product lets you put multiple current readers around specific
> circuits, and feed the measurements all to a single device that reads up
> to
> about nine circuits. This collector is then uplinked by RS-485 to
> ethernet, and to software on your PC. It's under $1K, and at least it's
> flexible to reorganize the groups of circuits you bill for, and
> consolidates
> data collection to one place. The software doesn't look beautiful to be
> sure, but I don't find many competitors either.
>
> The open part of the market is the consumer who wants to measure and
> manage
> energy utilization on 10 circuits in order to cut a $500 monthly bill to
> $400. It's hard to justify spending $400 * 10 in dedicated monitors on
> your fuse panel. It's barely acceptable to spend $1K for the Satec
> solution. What would make a lot more sense to me would be some kind of
> meter like the Kill-a-watt that has a wireless uplink to a central
> computer.
> But price point for that thing would need to be around $100 / meter,
> otherwise you don't pay back the investment fast enough to make it worth
> doing out of pocket. I wasn't able to find this product. Everything
> I
> could find was $400+ per meter.
>
> --
> Will
Thank you very much, you have been clear and concise.
req
|
|
|
|
|