|
Home > Archive > Home Repair forum > April 2008 > Rewiring a Hardwired Smoke Detector WITH THE POWER ON
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 |
Rewiring a Hardwired Smoke Detector WITH THE POWER ON
|
|
| gobofraggle@gmail.com 2008-04-01, 8:26 pm |
| I have a hardwired smoke detector that is old and outdated, that I'd
like to switch with a new unit. The only problem is that I can't
shut
off the power to the alarm before I disconnect it and reconnect the
new one. I'm going to have to do the take-down and installation
while
the power is LIVE.
I live in a high-rise apartment building and the smoke detector is
powered not by my unit's individual power, but off of a line brought
in from a common hallway. There is no way to cut power to the smoke
detector without cutting power to all the lights in the common
hallway, which is impossible.
So, how can I safely (or as safely as possible) change this detector
with a new one? If I don't touch certain wires together, will I be
OK? What are the chances I would get shocked?
I know your first inclination will be to tell me to get the circuit
turned off or call an electrician, but please (at least
hypothetically) assume that neither of those options are possible.
| |
| ransley 2008-04-01, 8:26 pm |
| On Apr 1, 5:32=A0pm, gobofrag...@gmail.com wrote:
> I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. =A0The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. =A0I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. =A0There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? =A0If I don't touch certain wires together, will I be
> OK? =A0What are the chances I would get shocked?
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
When I wire with power on I carefully remove wire nuts or screws with
a rubber insulated screwdriver and carefully rewire it, but if its a
building unit why bother it probably works, test it, I cant believe it
will set off others, but maybe call the manager. Gee, Free electric is
what I see from the building, or maybe you know that, but you will get
caught eventualy.
| |
| Jeff Wisnia 2008-04-01, 8:26 pm |
| gobofraggle@gmail.com wrote:
> I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? If I don't touch certain wires together, will I be
> OK? What are the chances I would get shocked?
>
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
Do you know if your smoke detector is "powered" by a 120 volt AC line or
by a low voltage line?
Do you know if the smoke detector sends a signal back to an alarm panel
to notify an alarm company that it's been tripped, or does it just sound
off in your place?
Do you know whether your "new" detector will be electrically and
operationally compatible with the existing system(s) in all respects?
If you aren't certain about all the above, stay away from that job.
Further, I'd suggest you'd be much better off taking the matter up with
the apartment building's management (if you haven't already) before you
do anything to the existing detector. I'd hazard a guess that they have
the right to be in control of things like that.
Play it safe, guy.
Jeff
--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.
| |
| Mikepier 2008-04-01, 8:26 pm |
| On Apr 1, 6:32=A0pm, gobofrag...@gmail.com wrote:
> I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. =A0The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. =A0I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. =A0There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? =A0If I don't touch certain wires together, will I be
> OK? =A0What are the chances I would get shocked?
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
Most of those 110V smoke detectors have a quick-disconnect plastic
connector that you should be able to work with while the power is
live. You would have to open up the detector and see if it does have
one of those connectors. And plus you would have to make sure the new
detector has a similiar connector. Usually they are interchangeable.
If the old unit is hardwired with no connector, I would try to cut the
power before working on it.
| |
| Colbyt 2008-04-01, 8:26 pm |
|
<gobofraggle@gmail.com> wrote in message
news:e9bdb1e6-20df-4a3a-ba3a-12a995298601@e67g2000hsa.googlegroups.com...
>I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? If I don't touch certain wires together, will I be
> OK? What are the chances I would get shocked?
>
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
I answer the questions without making judgments.
Hypothetically speaking, there is no way to get shocked or damage anything
if you work with one wire at a time and do not ground yourself while
touching the bare part of the hot (usually black or red) wire.
If I were to do something like this I would do the bare or green wire first,
the white wire second and the hot wire last. Once I had all the wires
connected to the new modular plug, I would plug it in and test it before
attached it to the box.
Note there may be an inter-connection wire (usually yellow that must also be
connected. This has no juice and can be done at any time.
Also the base plate may need to be changed even if it is the same brand.
--
Colbyt
Please come visit www.househomerepair.com
| |
|
| If you pop the breaker how will you restore power? If you get shocked will
you fall?
| |
| Norminn 2008-04-01, 8:26 pm |
| Jeff Wisnia wrote:
> gobofraggle@gmail.com wrote:
>
>
>
>
> Do you know if your smoke detector is "powered" by a 120 volt AC line
> or by a low voltage line?
>
> Do you know if the smoke detector sends a signal back to an alarm
> panel to notify an alarm company that it's been tripped, or does it
> just sound off in your place?
>
> Do you know whether your "new" detector will be electrically and
> operationally compatible with the existing system(s) in all respects?
>
> If you aren't certain about all the above, stay away from that job.
>
> Further, I'd suggest you'd be much better off taking the matter up
> with the apartment building's management (if you haven't already)
> before you do anything to the existing detector. I'd hazard a guess
> that they have the right to be in control of things like that.
>
> Play it safe, guy.
>
> Jeff
>
Not to mention doing something that might disable the entire system. I
have no clue whether that is possible, but you have no right to mess
with it. Let the building management replace it or embroider a pretty
doily to cover it up.
| |
| ransley 2008-04-01, 8:26 pm |
| On Apr 1, 6:03=A0pm, Norminn <norm...@earthlink.net> wrote:
> Jeff Wisnia wrote:
>
>
>
>
>
>
>
>
>
>
>
>
> Not to mention doing something that might disable the entire system. =A0I
> have no clue whether that is possible, but you have no right to mess
> with it. =A0Let the building management replace it or embroider a pretty
> doily to cover it up.- Hide quoted text -
>
> - Show quoted text -
Yes if it is a building supplied system you should not mess with it,
its not yours, its under the owners controll and you could trigger an
event you dont want. So it old looking , so what.
| |
| AZ Nomad 2008-04-01, 8:26 pm |
| On Tue, 01 Apr 2008 18:03:09 -0500, Norminn <norminn@earthlink.net> wrote:
>Jeff Wisnia wrote:
>Not to mention doing something that might disable the entire system. I
>have no clue whether that is possible, but you have no right to mess
>with it. Let the building management replace it or embroider a pretty
>doily to cover it up.
You could conceivable damager every detector on the system depending on the
design and where you sent 110.
| |
| gobofraggle@gmail.com 2008-04-01, 8:26 pm |
| The unit is a line voltage unit, not low voltage. The smoke detector
is stand-alone and does not signal back to a building-wide alarm
system. And the new detector is compatible with the old one.
Someone mentioned that I should use a special screwdriver. Where can
I find something like this and what does it look like?
So as long as I don't touch two of the same wires at the same time,
I'll be OK? How can I not ground myself? If I'm on a ladder wearing
rubber-soled sneakers, would that take care of it?
On Apr 1, 7:59=A0pm, Jeff Wisnia <jwis...@conversent.net> wrote:
> gobofrag...@gmail.com wrote:
>
>
>
>
> Do you know if your smoke detector is "powered" by a 120 volt AC line or
> by a low voltage line?
>
> Do you know if the smoke detector sends a signal back to an alarm panel
> to notify an alarm company that it's been tripped, or does it just sound
> off in your place?
>
> Do you know whether your "new" detector will be electrically and
> operationally compatible with the existing system(s) in all respects?
>
> If you aren't certain about all the above, stay away from that job.
>
> Further, I'd suggest you'd be much better off taking the matter up with
> the apartment building's management (if you haven't already) before you
> do anything to the existing detector. I'd hazard a guess that they have
> the right to be in control of things like that.
>
> Play it safe, guy.
>
> Jeff
>
> --
> Jeffry Wisnia
> (W1BSV + Brass Rat '57 EE)
> The speed of light is 1.8*10^12 furlongs per fortnight.- Hide quoted text =
-
>
> - Show quoted text -
| |
|
|
<gobofraggle@gmail.com> wrote in message
news:e9bdb1e6-20df-4a3a-ba3a-12a995298601@e67g2000hsa.googlegroups.com...
>I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? If I don't touch certain wires together, will I be
> OK? What are the chances I would get shocked?
>
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
No problem working 120V live if you know what you are doing. Sounds like you
don't, than you must ask yourself what would be the upside vs. the downside
when the building maintenance staff take care of this at no cost to you.
Shouldn't liability and ventricular fibrillation should be a major factor to
you?
| |
| S. Barker 2008-04-01, 8:27 pm |
| wooden ladder, rubber tennis shoes, AND only work one wire at a time and
don't touch the metal box it's mounted in.
s
Back when i was 13, i landed about 4 dozen duplex outlets and 8 or nine
switches all with the power on. Just have to take your time and handle one
wire at a time.
<gobofraggle@gmail.com> wrote in message
news:e9bdb1e6-20df-4a3a-ba3a-12a995298601@e67g2000hsa.googlegroups.com...
>I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? If I don't touch certain wires together, will I be
> OK? What are the chances I would get shocked?
>
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
| |
| S. Barker 2008-04-01, 8:27 pm |
| Pat makes a good point. What if the breaker pops? What if you reach up
there and cut all the wires at once? (use an old cutter, it will be hard on
the edge of it) The breaker will be popped, and you can continue with your
changing out of the unit. Then at some point, the breaker will get reset by
someone eh????
s
<gobofraggle@gmail.com> wrote in message
news:e9bdb1e6-20df-4a3a-ba3a-12a995298601@e67g2000hsa.googlegroups.com...
>I have a hardwired smoke detector that is old and outdated, that I'd
> like to switch with a new unit. The only problem is that I can't
> shut
> off the power to the alarm before I disconnect it and reconnect the
> new one. I'm going to have to do the take-down and installation
> while
> the power is LIVE.
>
> I live in a high-rise apartment building and the smoke detector is
> powered not by my unit's individual power, but off of a line brought
> in from a common hallway. There is no way to cut power to the smoke
> detector without cutting power to all the lights in the common
> hallway, which is impossible.
>
>
> So, how can I safely (or as safely as possible) change this detector
> with a new one? If I don't touch certain wires together, will I be
> OK? What are the chances I would get shocked?
>
>
> I know your first inclination will be to tell me to get the circuit
> turned off or call an electrician, but please (at least
> hypothetically) assume that neither of those options are possible.
| |
|
| Someone mentioned that I should use a special screwdriver. Where can
I find something like this and what does it look like?
So as long as I don't touch two of the same wires at the same time,
I'll be OK? How can I not ground myself? If I'm on a ladder wearing
rubber-soled sneakers, would that take care of it?
-----------------------------------------------------------------------
Looks like you have to do this anyway so here are some advice.
1 Work with a buddy so he/she could call 911 and get help.
2 Use non conducting ladder. Ware electrical insulating gloves and shoes.
3 Don't need special screwdriver, wrap conducting part with electrical
tape.
4 Work with one hand only, put the other hand in your back pocket.
Remember it doesn't take much, as little as 6 milliamps, to go into
ventricular fibrillation or cardiac arrest.
| |
|
| On Tue, 1 Apr 2008 15:32:00 -0700 (PDT), gobofraggle@gmail.com wrote:
>I have a hardwired smoke detector that is old and outdated, that I'd
>like to switch with a new unit. The only problem is that I can't
>shut
>off the power to the alarm before I disconnect it and reconnect the
>new one. I'm going to have to do the take-down and installation
>while
>the power is LIVE.
>
>I live in a high-rise apartment building and the smoke detector is
>powered not by my unit's individual power, but off of a line brought
>in from a common hallway. There is no way to cut power to the smoke
>detector without cutting power to all the lights in the common
>hallway, which is impossible.
>
>
>So, how can I safely (or as safely as possible) change this detector
>with a new one? If I don't touch certain wires together, will I be
>OK? What are the chances I would get shocked?
>
>
>I know your first inclination will be to tell me to get the circuit
>turned off or call an electrician, but please (at least
>hypothetically) assume that neither of those options are possible.
The way you do it safely is to turn the power off.
Anyone that tells you "It can't be turned off" is lying
| |
| Mike Dobony 2008-04-01, 9:26 pm |
| On Tue, 1 Apr 2008 17:22:31 -0700, Frank wrote:
> Someone mentioned that I should use a special screwdriver. Where can
> I find something like this and what does it look like?
>
> So as long as I don't touch two of the same wires at the same time,
> I'll be OK? How can I not ground myself? If I'm on a ladder wearing
> rubber-soled sneakers, would that take care of it?
>
> -----------------------------------------------------------------------
>
>
> Looks like you have to do this anyway so here are some advice.
>
> 1 Work with a buddy so he/she could call 911 and get help.
>
> 2 Use non conducting ladder. Ware electrical insulating gloves and shoes.
>
> 3 Don't need special screwdriver, wrap conducting part with electrical
> tape.
>
> 4 Work with one hand only, put the other hand in your back pocket.
>
>
> Remember it doesn't take much, as little as 6 milliamps, to go into
> ventricular fibrillation or cardiac arrest.
The key is to not let the current go across the heart. I just did some
wiring and forgot the outlet next to the switch was live and on another
circuit. I touched it and held for about a second before I realized what
was happening. Work with 120 enough and it barely fazes you. I don't
worry too much about 120 and occasionally work with live wires. You bigger
concerns are compatibility with the existing system, likely interwired so
that when one goes off they all go off, and also with not destroying the
rest of the system. I seriously doubt it is connected to the lighting
system as the smoke alarms are supposed to be on their own breaker.
| |
| Nate Nagel 2008-04-02, 3:25 am |
| Mike Dobony wrote:
> On Tue, 1 Apr 2008 17:22:31 -0700, Frank wrote:
>
>
>
>
>
> The key is to not let the current go across the heart. I just did some
> wiring and forgot the outlet next to the switch was live and on another
> circuit. I touched it and held for about a second before I realized what
> was happening. Work with 120 enough and it barely fazes you. I don't
> worry too much about 120 and occasionally work with live wires. You bigger
> concerns are compatibility with the existing system, likely interwired so
> that when one goes off they all go off, and also with not destroying the
> rest of the system. I seriously doubt it is connected to the lighting
> system as the smoke alarms are supposed to be on their own breaker.
I've heard it both ways; makes more sense to me to go ahead and put it
on the lighting circuit, reason being that the homeowner will notice if
the lights aren't working but if the breaker dedicated to a run of
detectors trips he may not notice that and be unprotected.
Of course, the local AHJ has the final word on what's cool and what isn't.
nate
--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel
| |
| Tony Hwang 2008-04-02, 3:25 am |
| Nate Nagel wrote:
> Mike Dobony wrote:
>
>
>
> I've heard it both ways; makes more sense to me to go ahead and put it
> on the lighting circuit, reason being that the homeowner will notice if
> the lights aren't working but if the breaker dedicated to a run of
> detectors trips he may not notice that and be unprotected.
>
> Of course, the local AHJ has the final word on what's cool and what isn't.
>
> nate
>
Remember without ground path urrent can't flow. Wear rubber sole shoes.
Only touch one wire at a time. Don'r make your body a current path.
I often work on live 120 or 220V lines. As long as this is kept in mind,
it is OK. More is needed? Wear a pair of thin rubber gloves. Or use a
tool with insulated grip.
| |
| websurf1@cox.net 2008-04-02, 3:25 am |
| On Apr 1, 6:29 pm, Mike Dobony <sw...@notasarian-host.net> wrote:
> On Tue, 1 Apr 2008 17:22:31 -0700, Frank wrote:
>
>
>
>
>
>
>
>
>
> The key is to not let the current go across the heart. I just did some
> wiring and forgot the outlet next to the switch was live and on another
> circuit. I touched it and held for about a second before I realized what
> was happening. Work with 120 enough and it barely fazes you. I don't
> worry too much about 120 and occasionally work with live wires. You bigger
> concerns are compatibility with the existing system, likely interwired so
> that when one goes off they all go off, and also with not destroying the
> rest of the system. I seriously doubt it is connected to the lighting
> system as the smoke alarms are supposed to be on their own breaker.
If by "barely fazes you", you mean it's less likely to hurt you, well,
yer nuts.
You've just been lucky so far.
The OP probably shouldn't be doing this. The setup doesn't make
sense, and he doesn't know enough to be playing with live wires.
| |
| Mike Dobony 2008-04-03, 9:25 am |
| On Tue, 01 Apr 2008 23:00:58 -0400, Nate Nagel wrote:
> Mike Dobony wrote:
>
> I've heard it both ways; makes more sense to me to go ahead and put it
> on the lighting circuit, reason being that the homeowner will notice if
> the lights aren't working but if the breaker dedicated to a run of
> detectors trips he may not notice that and be unprotected.
>
> Of course, the local AHJ has the final word on what's cool and what isn't.
>
> nate
That is assuming that they don't have a battery backup (never seen such an
animal) and that you are dealing with a homeowner, not a commercial
apartment complex, as in the OP's case.
| |
| Mark H 2008-04-03, 5:25 pm |
|
"Colbyt" <colbyt@-SPAMBLOCK-lexkyweb.com> wrote in message
news:99ednRYxwtfII2_anZ2dnUVZ_vKunZ2d@insightbb.com...
>
> <gobofraggle@gmail.com> wrote in message
> news:e9bdb1e6-20df-4a3a-ba3a-12a995298601@e67g2000hsa.googlegroups.com...
>
>
>
> I answer the questions without making judgments.
>
> Hypothetically speaking, there is no way to get shocked or damage anything
> if you work with one wire at a time and do not ground yourself while
> touching the bare part of the hot (usually black or red) wire.
>
> If I were to do something like this I would do the bare or green wire
> first, the white wire second and the hot wire last. Once I had all the
> wires connected to the new modular plug, I would plug it in and test it
> before attached it to the box.
>
> Note there may be an inter-connection wire (usually yellow that must also
> be connected. This has no juice and can be done at any time.
>
> Also the base plate may need to be changed even if it is the same brand.
>
>
> --
> Colbyt
> Please come visit www.househomerepair.com
>
Hot comes off first goes on the last
|
|
|
|
|