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randomidiot
May 12, 2006

by Fluffdaddy

(and can't post for 11 years!)

The house I'm in has the original 19 year old smoke detectors; wired so that if one goes off, they all go off. They have a dedicated breaker as well. I do plan to replace them pretty soon..

When we moved in, none of them had batteries installed. This model apparently doesn't chirp about a low battery until it's been connected to a battery at least once. :sigh:

Right now the batteries are all less than a year old, except for the super high one I mentioned (that one's probably about 3 years old).

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Guy Axlerod
Dec 29, 2008
I guess what I don't understand is why someone would pay extra for a hard-wired system when they still have to replace the batteries?

I understand you get the whole-house alarm, but couldn't a wireless system do the same thing?

grover
Jan 23, 2002

PEW PEW PEW
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Guy Axlerod posted:

I guess what I don't understand is why someone would pay extra for a hard-wired system when they still have to replace the batteries?

I understand you get the whole-house alarm, but couldn't a wireless system do the same thing?
It's required by code and pretty cheap for new construction.

ncumbered_by_idgits
Sep 20, 2008

kastein posted:

This one almost SHOULD trip the breaker, seeing as that's a fairly hot arc for the split second where the entire outlet glows when you rip the plug out of the outlet with a 7 amp motor spinning at warp nine on the other end of the cord.

Agreed, but I would still classify it as a nuisance if I had to go reset a breaker every time I accidentally strayed too far from the receptacle with my vacuum and it came unplugged.

Motronic
Nov 6, 2009

grover posted:

Not exactly; AFCI breakers include GFI as well as arc detection,

That would be a CAFCI, not an AFCI.

kastein
Aug 31, 2011

Moderator at http://www.ridgelineownersclub.com/forums/and soon to be mod of AI. MAKE AI GREAT AGAIN. Motronic for VP.
I thought CAFCI was combined series and parallel AFCI, not combined AFCI and GFCI, but I haven't been too clear on it.

grover
Jan 23, 2002

PEW PEW PEW
:circlefap::circlefap::circlefap:
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kastein posted:

I thought CAFCI was combined series and parallel AFCI, not combined AFCI and GFCI, but I haven't been too clear on it.
Yeah, the "combination" part of CAFCI is related to the combinations of arcs it detects, not ground-fault. All AFCI breakers made since 2008 are required to be combination, so most people don't really bother using the term- we just call them AFCI.

Most AFCI breakers (new and old) have integrated ground fault detection as part of the fault detection circuitry, though do NOT qualify as GFCI because tolerance is set higher- 30ma vice 5ma for GFCI.

ntd
Apr 17, 2001

Give me a sandwich!

some texas redneck posted:

The house I'm in has the original 19 year old smoke detectors; wired so that if one goes off, they all go off. They have a dedicated breaker as well. I do plan to replace them pretty soon..

When we moved in, none of them had batteries installed. This model apparently doesn't chirp about a low battery until it's been connected to a battery at least once. :sigh:

Right now the batteries are all less than a year old, except for the super high one I mentioned (that one's probably about 3 years old).

I believe now that the smoke detectors need to be tied into a lighting/general load instead of a dedicated circuit. So that people won't just turn them off. More of the "protecting people from themselves" stuff, which is great because holy poo poo do people need that.

stupid puma
Apr 25, 2005

I've got a couple of questions. I don't know much about electrical so please bear with me.

I purchased a house recently that was built in 1957. Every outlet in the house is 3 prong and there is a newer breaker box installed. However, I've come to find that only the rooms that have been remodeled (Kitchen and basement) have actual grounded outlets. The other rooms (aside from the bathroom) don't have GFCI outlets. Is that something that our appraiser/inspector should have picked up on and alerted us to? It's against code, right?

As for getting my house up to code- I'm sure the most effective option would be to run new romex or a separate ground to each outlet, but I don't really want to spend the time and/or money to do that. So, should I install 1) GFCI outlets in the rooms with no grounds, or 2) a GFCI breaker at the box for those rooms, or 3) an arc fault breaker at the box for those rooms? Would each of these three options bring my house up to code? Which is typically most preferable and why? None of these options will protect my electronics from frying if there is faulty wiring, they'll just prevent me from dying, right?

Is it possible that there is some sort of other protection at the box that I don't know about that would make my house up to code? My understanding based on this thread is that if you change the box that all electrical downstream needs to be brought up to code. It seems like a licensed guy did the box wiring - how could he get away with leaving half the house ungrounded?

Motronic
Nov 6, 2009

stupid puma posted:

It's against code, right?

If you were building a new home it would be. Or remodeling. Electrical and building codes are not enforced ex-post-facto. Some things (not those) may be required on a change of ownership/C of O.

grover
Jan 23, 2002

PEW PEW PEW
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stupid puma posted:

I've got a couple of questions. I don't know much about electrical so please bear with me.

I purchased a house recently that was built in 1957. Every outlet in the house is 3 prong and there is a newer breaker box installed. However, I've come to find that only the rooms that have been remodeled (Kitchen and basement) have actual grounded outlets. The other rooms (aside from the bathroom) don't have GFCI outlets. Is that something that our appraiser/inspector should have picked up on and alerted us to? It's against code, right?
Codes aren't retroactive, but it was never to code to install 3-prong grounded outlets without either grounding them, or protecting them via GFCI and clearly labeling them as GFCI-ungrounded. Sounds like your inspector missed it.

The easiest safe/legal way to retrofit is to install GFCIs. You don't need a GFCI per receptacle; one GFCI can protect the entire string. Find where the first one in the string is, and install a GFCI there.

grover fucked around with this message at 22:54 on Sep 3, 2013

kid sinister
Nov 16, 2002

stupid puma posted:

I've got a couple of questions. I don't know much about electrical so please bear with me.

I purchased a house recently that was built in 1957. Every outlet in the house is 3 prong and there is a newer breaker box installed. However, I've come to find that only the rooms that have been remodeled (Kitchen and basement) have actual grounded outlets. The other rooms (aside from the bathroom) don't have GFCI outlets. Is that something that our appraiser/inspector should have picked up on and alerted us to? It's against code, right?

As for getting my house up to code- I'm sure the most effective option would be to run new romex or a separate ground to each outlet, but I don't really want to spend the time and/or money to do that. So, should I install 1) GFCI outlets in the rooms with no grounds, or 2) a GFCI breaker at the box for those rooms, or 3) an arc fault breaker at the box for those rooms? Would each of these three options bring my house up to code? Which is typically most preferable and why? None of these options will protect my electronics from frying if there is faulty wiring, they'll just prevent me from dying, right?

Is it possible that there is some sort of other protection at the box that I don't know about that would make my house up to code? My understanding based on this thread is that if you change the box that all electrical downstream needs to be brought up to code. It seems like a licensed guy did the box wiring - how could he get away with leaving half the house ungrounded?

I wrote up a 3 prong upgrade post that's linked in the OP. Check it out and do the tests listed. You might be able to ground your outlets legally with the existing wiring. I was able to, and my house was built a year before yours. That linked post also answers questions 1) and 2).

As for 3), AFCIs protect differently from GFCIs. Still, swapping in AFCI breakers would bring you up to another part of the code, namely, living space protection. For the most part AFCIs are required everywhere that GFCIs are not, and GFCI protection is required within 6' of any sink, outdoors, in garages and unfinished basements. The big exception to this is dedicated circuits. For example, laundry, furnace/AC, etc.

crocodile
Jun 19, 2004

ntd posted:

I believe now that the smoke detectors need to be tied into a lighting/general load instead of a dedicated circuit. So that people won't just turn them off. More of the "protecting people from themselves" stuff, which is great because holy poo poo do people need that.

off the top of my head i can't remember any actual code pertaining to smoke detectors in the NEC, i thought they were part of building codes? i do know there's a fine print note saying that since smoke detectors are required in bedrooms they are required to be AFCI protected. we automatically put them on one of the bedroom circuits to protect them under that rooms AFCI breaker.

stupid puma posted:

My understanding based on this thread is that if you change the box that all electrical downstream needs to be brought up to code. It seems like a licensed guy did the box wiring - how could he get away with leaving half the house ungrounded?

this completely depends on your city/jurisdiction. we do A LOT of panel/service changes in western washington and are not required to bring the rest of the house up to code. for a lot of people it's just insanely cost prohibitive and i personally don't think a homeowner should have to bear that burden if there is some sort of mechanical failure in their panel or whatever that requires it to be replaced.

Dirk Digglet
Aug 17, 2009

When I close my eyes, I see this thing, a sign, I see this name in bright blue neon lights with a purple outline
EDIT: Found an easier solution

Thanks for the 3-prong upgrade post.

Dirk Digglet fucked around with this message at 09:32 on Sep 4, 2013

kastein
Aug 31, 2011

Moderator at http://www.ridgelineownersclub.com/forums/and soon to be mod of AI. MAKE AI GREAT AGAIN. Motronic for VP.
From what I've been told, smokes should be on their own breaker and it SHOULDN'T be AFCI. My understanding was that you want them powered no matter what. Maybe I'm wrong?

Papercut
Aug 24, 2005
Yeah why would you want fire alarm to be on a circuit that has extra ways to trigger open? I don't do residential at all so the code may be different there, but in general you would never put your fire alarm equipment on a GFCI or AFCI breaker.

grover
Jan 23, 2002

PEW PEW PEW
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IRC R313 covers smoke alarms in houses. It requires smoke alarms to be powered from building power with battery back-up. It's silent on whether it needs a dedicated circuit or can share, which means either way is fine, but they all have to be interconnected so that if one goes off, they all go off.

One advantage of sharing a lighting circuit is that you'd know if the breaker tripped and be able to address it. Since you have battery backup, losing power for short periods of time isn't all that big a deal.

grover fucked around with this message at 15:57 on Sep 4, 2013

rekamso
Jan 22, 2008
How does one figure out the amps that are currently being delivered to a house?

In this case, the panel is a 200amp panel but the main lugs have been bypassed and service is being backfed (?) through a 100amp breaker. The house is 2000 sq ft built in 1979; electric baseboard heating and all-electric appliances (no natural gas). Lovely photo (yes, that's aluminum wiring as well):



I contacted Seattle City Light and they said "we don't have that info" and "look at the panel" which doesn't tell me anything since the panel was clearly modified at one point.

ncumbered_by_idgits
Sep 20, 2008

rekamso posted:

How does one figure out the amps that are currently being delivered to a house?

In this case, the panel is a 200amp panel but the main lugs have been bypassed and service is being backfed (?) through a 100amp breaker. The house is 2000 sq ft built in 1979; electric baseboard heating and all-electric appliances (no natural gas). Lovely photo (yes, that's aluminum wiring as well).

I contacted Seattle City Light and they said "we don't have that info" and "look at the panel" which doesn't tell me anything since the panel was clearly modified at one point.

If you want to know how many amps you are using at any point in time you will need to put a clamp-type ammeter on the main feeders wires.

If you meant you want to know the service size, the utility should be able to give you that info, you just need to talk to the right person. Otherwise look at the meter, it should have a label telling you the amps it's rated for. Or look at the main feeder wires. #3 or so means 100 amp, 4/0 give or take is a 200 amp service. I can't tell from the pic.

That panel is in need of some attention though.

ncumbered_by_idgits fucked around with this message at 22:19 on Sep 4, 2013

babyeatingpsychopath
Oct 28, 2000
Forum Veteran


rekamso posted:

How does one figure out the amps that are currently being delivered to a house?

In this case, the panel is a 200amp panel but the main lugs have been bypassed and service is being backfed (?) through a 100amp breaker. The house is 2000 sq ft built in 1979; electric baseboard heating and all-electric appliances (no natural gas). Lovely photo (yes, that's aluminum wiring as well):

I contacted Seattle City Light and they said "we don't have that info" and "look at the panel" which doesn't tell me anything since the panel was clearly modified at one point.

If you want to know your load right now, you use an ammeter. If you want to replace the panel, you can use a years' worth of electricity bills to get your kW/kVA usage, or you do a service load calculation as per NEC article 220. If you want to know what your service is rated for, you look at the rating of your meter base and ask the power company what their transformer/service conductors are rated to provide.

Raised by Hamsters
Sep 16, 2007

and hopped up on bagels
Anyone know if the installation method being shown here http://www.amazon.com/gp/product/B002W6ZOCO/ref=oh_details_o00_s00_i01?ie=UTF8&psc=1 for an exterior light mount is OK? (Jam NM through exterior wall, caulk in place). I currently have full access to the inside of the wall cavity from the interior of the house. Don't really want to mess with the siding for this one if I can help it, so the small penetration appeals to me.

Not an Anthem
Apr 28, 2003

I'm a fucking pain machine and if you even touch my fucking car I WILL FUCKING DESTROY YOU.
Hi. Wiring question.

I work in a big building with one room that's setup as a shop and has I think two points of 3 phase hooked up (a knee mill and a table saw) in the shop.

A new client has given us a ton of equipment to test out and redesign and its a mix of 2 and 3 phase stuff (food service equipment, think toasters, convection ovens, etc). I think there is one 3 phase and a couple 2 phase and all fairly high amps, I think the big toaster is 16a?

Now, I know nothing about power and its not my job, but the guy whose job its supposed to be to figure out how to set this up wants to put it all in our shop because getting maintenance to run power to the things will be cheaper in his mind. They charged him ~140$ to drop 3 phase for the table saw last time which was just a wire coming out of the ceiling, a piece of conduit, the plug and terminating it. He's freaked out that running 2/3 phase to other areas will be thousands of dollars and maybe he is right, but we cannot have this equipment in our shop for a lot of reasons.

To someone who is totally ignorant in terms of power, what does it take to run 2 and 3 phase to the machines? Having a converter for the machines as a layman sounds like an expensive/bad idea and we could actually use the 3 phase plugs down the line. If there is existing laid single phase does that make it any easier to get 3 phase to it or is that dependent on totally different factors?

* Yes this is stupid and poorly planned but I am going to have to deal with all this.

Qwijib0
Apr 10, 2007

Who needs on-field skills when you can dance like this?

Fun Shoe

Not an Anthem posted:

To someone who is totally ignorant in terms of power, what does it take to run 2 and 3 phase to the machines? Having a converter for the machines as a layman sounds like an expensive/bad idea and we could actually use the 3 phase plugs down the line. If there is existing laid single phase does that make it any easier to get 3 phase to it or is that dependent on totally different factors?

As long as you are not going to need any 115/120V circuits, 3-phase is pretty simple. You've got 3 hots, ground, and maybe a neutral depending on how your shop is run-- between any two hots is going to be 208V (wye transformer) or 230 (delta transformer), so choose two with extra capacity and you've got your 2-phase "220" circuit to wire into an L6-30 or whatever you need.

Wiring 3-phase would just be attaching to all 3 hots. If your shop follows convention, L1 (X) is black, L2 (Y) is red and L3 (Z) is blue. YMMV wrt colors though.

If you're tracing back to the panel for some reason, the phases should be sequential down each side of the panel like so:

ckt 1 - ph1
ckt 3 - ph2
ckt 5 - ph3
ckt 7 - ph1
ckt 9 - ph2
ckt 11 - ph3

Not an Anthem
Apr 28, 2003

I'm a fucking pain machine and if you even touch my fucking car I WILL FUCKING DESTROY YOU.
Clarification: we can't do any of the work ourselves due to work contracts. We have electricians on staff who will be doing. I'm just trying to figure out the lowest cost to us as well as keep the equipment OUT of our wood/metal shop. Its not wood/metal working tools.

crocodile
Jun 19, 2004

rekamso posted:

How does one figure out the amps that are currently being delivered to a house?

In this case, the panel is a 200amp panel but the main lugs have been bypassed and service is being backfed (?) through a 100amp breaker. The house is 2000 sq ft built in 1979; electric baseboard heating and all-electric appliances (no natural gas). Lovely photo (yes, that's aluminum wiring as well):



I contacted Seattle City Light and they said "we don't have that info" and "look at the panel" which doesn't tell me anything since the panel was clearly modified at one point.

to me it just looks like they bypassed the lugs and are using that 100 amp breaker to feed the busbar? did someone tell you it's back feeding the service? from that picture the conductors look sized for 100 amps but it's hard to tell. do you have a picture of your meterbase? in this area it's weird that you'd have anything less than 200 amps in 1979 but i have seen it. regardless whoever said that panel needs some attention is right.

Maniaman
Mar 3, 2006
Crossposting from the Crappy Construction Tales thread:

This fabulous piece of work left by a contractor that we fired.



Pretty much every splice is free hanging, and there are about 10 circuits running through that since 2 gang box.

Voodoo
Jun 3, 2003

m2sbr what
I had an overhead light+fan installed in my bedroom last month - with dimmer/fan speed control on the wall switch. I put in some Philips LED bulbs (11W, dimmable) and things had been working fine since then. Today for some reason, maybe it was a power flicker from a storm or something, the LED bulbs started to flicker off briefly, maybe every 4-5 seconds. Before I had to step out of the house I was able to figure out the following: they only flicker when the light is turned on and set to full, and the fan is turned off. If the fan is on, or the bulb is set to any dimmed setting but max, the bulbs do not flicker. I tried re-seating the bulbs, no change, and at that point I had to leave. My wife was in bed when I got home, so I couldn't really fool with it anymore tonight.

Where should I start troubleshooting tomorrow? I suspect CFLs will not flicker, but I guess I'll start with that. Maybe test the bulbs in another light. Any other ideas as to what it might be? I'm hoping it's not some wiring issue, but I suppose I could ping on the contractor and see what they say.

kid sinister
Nov 16, 2002

Voodoo posted:

I had an overhead light+fan installed in my bedroom last month - with dimmer/fan speed control on the wall switch. I put in some Philips LED bulbs (11W, dimmable) and things had been working fine since then. Today for some reason, maybe it was a power flicker from a storm or something, the LED bulbs started to flicker off briefly, maybe every 4-5 seconds. Before I had to step out of the house I was able to figure out the following: they only flicker when the light is turned on and set to full, and the fan is turned off. If the fan is on, or the bulb is set to any dimmed setting but max, the bulbs do not flicker. I tried re-seating the bulbs, no change, and at that point I had to leave. My wife was in bed when I got home, so I couldn't really fool with it anymore tonight.

Where should I start troubleshooting tomorrow? I suspect CFLs will not flicker, but I guess I'll start with that. Maybe test the bulbs in another light. Any other ideas as to what it might be? I'm hoping it's not some wiring issue, but I suppose I could ping on the contractor and see what they say.

It's most likely the dimmer. Dimmable CFLs and LEDs aren't perfect. What's worse is that regular CFLs aren't compatible with regular dimmers.

ToxicFrog
Apr 26, 2008


I've got two troubleshooting questions. Please bear with me, I'm ok with DC but AC scares me and I don't know much about house wiring.

#1: a 15A breaker just tripped downstairs. The circuit it controls drives some lights and a dehumidifier. What's surprising about this is that the dehumidifier has been running for a while without problems, and doesn't trip the breaker when plugged into other circuits. I tried flipping the breaker back on and it seemed happy, but I heard a faint sizzling noise. Shut it back off and removed the coverplate.



Is it just me, or does that look kind of charred? If so, what do I do? Can I safely strip off the charred section and connect it to the other half of the breaker, or will I have to replace the entire breaker? Also, is this a sign that it just wasn't connected to the breaker properly, or that the wire is not rated for the amount of current through it, and I'll need to either rewire that entire circuit (please god no) or replace the breaker with one with a lower current limit? And if I'm completely wrong and it's meant to look like that, can I safely assume it was a transient increase in power draw from the dehumidifier that tripped it and hook everything back up again?


#2: there is a different circuit, also 15A, driving the wall sockets for three rooms in the basement. It looks fine under continuity testing, and the home inspector didn't catch anything wrong with it. When we plugged a UPS into it, though, the warning light lit up. Investigation with a multimeter revealed that there's about 40V between ground and neutral at the outlet! I had an electrician in and he determined that all of the outlets on this circuit have this problem, but also that ground and neutral for this circuit are properly bonded at the breaker box with 0V between them, and that there is continuity between ground at the outlet and ground at the breaker box.

The problem, whatever it is, is between the breaker box and the first outlet, which, due to the way this is cabled in, would require disassembling most of the wall of at least two rooms to get at - the fucker runs horizontally and is bracketed to the interior of the wall, so we can't just disconnect it at the outlet and then pull it out. The electrician said that this should be fixed, but since it is still connected to ground it'll still provide protection against ground faults and trip the breaker if something goes wrong - so we can safely wait until we're doing something else that requires taking the entire north half of the basement apart, and get it fixed then.

What causes this? How much of a pain is it going to be to fix once we have the wall open? And is the electrician right about this not being an immediate safety concern?

vv Hey weird voltages on ground buddy

ToxicFrog fucked around with this message at 22:28 on Sep 14, 2013

Bobulus
Jan 28, 2007

Googled around and am getting different answers in different places. Grounding issue:

- Old, rental, house
- 3 prong outlets have been used to replace most of the original 2-prong outlets, but a cheap outlet tester says that every outlet in the house (other than the remodeled kitchen) is lacking a ground.
- Opened up an outlet in one of the bedrooms, and there is indeed a green ground wire, but it's not hooked to the outlet.
- I was hoping this was going to be an easy fix, but when I get out my multimeter, I'm getting weird AC voltages:

Hot to neutral: 126V
Hot to ground: 65V
Neutral to ground: 50V
Hot to metal outlet box: 25V

So... what gives? Is that green grounding wire hooked to nothing? Would hooking it up be better or worse than leaving it disconnected? I can buy some GFCI outlets, like the OP mentioned, but I'm really more curious about what these readings mean.

(Some of the forums I looked at seemed to indicate that you'd get funny readings with a cheapo multimeter if the system was not under load, so I checked. Same readings both with and without a lamp plugged in and turned on)

edit: The house has an office-style tiled ceiling, so I imagine they ran wires to these outlets that way. May see if I can borrow a ladder and peek my head up there, see if there's any indication how all this is run together.

Bobulus fucked around with this message at 19:09 on Sep 14, 2013

grover
Jan 23, 2002

PEW PEW PEW
:circlefap::circlefap::circlefap:
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:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:

ToxicFrog posted:

Is it just me, or does that look kind of charred? If so, what do I do? Can I safely strip off the charred section and connect it to the other half of the breaker, or will I have to replace the entire breaker? Also, is this a sign that it just wasn't connected to the breaker properly, or that the wire is not rated for the amount of current through it, and I'll need to either rewire that entire circuit (please god no) or replace the breaker with one with a lower current limit? And if I'm completely wrong and it's meant to look like that, can I safely assume it was a transient increase in power draw from the dehumidifier that tripped it and hook everything back up again?
Yes, that cable and breaker are both damaged. Replace the breaker for sure (they're cheap) and cut the wire back past where the insulation is visibly damaged before reconnecting. If it's #14 or larger, it's properly sized. I suspect the breaker lug was not properly tightened, as loose connectors can cause arcing (which was likely the crackling you heard) which cause heating and damage. Tightening lugs like this is actually supposed to be done on a regular basis as they can loosen up through time; pros will use thermal cameras to check for tightness as loose lugs show up as hot spots. In this case it probably just wasn't tightened right when it was installed.

Turn power off to the whole panel and give that wire a tug- if it comes out, that was for sure your problem. I would torque down every other bolt in the panel at the same time.

A loose neutral or ground is likely the cause of the 40V readings- readings like that are often phantom voltages due to poor connections. Probably the ground in this cases as you'd likely have experienced issues if the neutral was loose. Check all the ground connections in all the boxes in that circuit if you can.

grover fucked around with this message at 20:35 on Sep 14, 2013

Motronic
Nov 6, 2009

Bobulus posted:

Neutral to ground: 50V


If that truly is a ground, that right there is a big red flag that there is something terribly wrong, and not just with those outlets.

grover
Jan 23, 2002

PEW PEW PEW
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:

Bobulus posted:

Googled around and am getting different answers in different places. Grounding issue:

- Old, rental, house
- 3 prong outlets have been used to replace most of the original 2-prong outlets, but a cheap outlet tester says that every outlet in the house (other than the remodeled kitchen) is lacking a ground.
- Opened up an outlet in one of the bedrooms, and there is indeed a green ground wire, but it's not hooked to the outlet.
- I was hoping this was going to be an easy fix, but when I get out my multimeter, I'm getting weird AC voltages:

Hot to neutral: 126V
Hot to ground: 65V
Neutral to ground: 50V
Hot to metal outlet box: 25V

So... what gives? Is that green grounding wire hooked to nothing? Would hooking it up be better or worse than leaving it disconnected? I can buy some GFCI outlets, like the OP mentioned, but I'm really more curious about what these readings mean.

(Some of the forums I looked at seemed to indicate that you'd get funny readings with a cheapo multimeter if the system was not under load, so I checked. Same readings both with and without a lamp plugged in and turned on)

edit: The house has an office-style tiled ceiling, so I imagine they ran wires to these outlets that way. May see if I can borrow a ladder and peek my head up there, see if there's any indication how all this is run together.
Yeah, that green wire should be connected! I suspect the ground is broken or disconnected elsewhere, too- the phantom voltage is due to the ground wire not being connected to anything, with random voltages being induced by line induction. When the electricians say to put a load on, they mean to use an old style analog voltmeter with the moving needle, since any stray phantom voltage will be cleared by the coil. Digital voltmeters (the good and the cheap) have a much higher impedance and don't really clear it. You could also try a continuity check between the neutral and ground.

I'd take this to your landlord though and get him to bring an electrician in to take a look at it. It's a serious safety issue no matter which way it ends up.

grover fucked around with this message at 20:36 on Sep 14, 2013

Bobulus
Jan 28, 2007

I'm hesitant to deal with the rental people, because their contract is just littered with clauses that say that I have to pay for poo poo. Didn't have a lot of choice, as it's very much a seller's market here and everyone else was the same way. For example, if the dishwasher breaks, the contract says that I have to pay for repairs, with an oral statement (ie, not enforceable) that this only applies if I deliberately break it. When the dryer broke, they fixed it without charging me, but I'm very leery about any sort of "optional" repairs, as I'm sure they'll find some way to stick it to me, even if it just means making up bullshit to keep my security deposit.

Other than the kitchen appliances (which are grounded), the only things in this house that actually use a 3-prong plug are a desktop computer and a treadmill, with the computer being extension-corded from the kitchen and the treadmill currently unused. My impulse is to get a gfci outlet for the treadmill and call it good, but maybe I should make a fuss with the landlord, I'm not sure.

I guess I'm mainly wondering if hooking up a broken ground (IE, the voltage difference between neutral and ground) is worse than having no ground at all hooked up. Which is less likely to fry my treadmill?

quote:

You could also try a continuity check between the neutral and ground.

You check this with the breaker off, right? I just tried that and could get no continuity between the two.

Bobulus fucked around with this message at 21:18 on Sep 14, 2013

grover
Jan 23, 2002

PEW PEW PEW
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:

Bobulus posted:

You check this with the breaker off, right? I just tried that and could get no continuity between the two.
On or off shouldn't matter; if you have no continuity, there is no ground.

This is not a "you broke your dishwasher" kind of thing; this is a pre-existing building code violation the landlord should be responsible for fixing. It's the type of thing that can leave the unit uninhabitable until repaired.

Possible caveat: are these outlets GFCI protected? That's the only way they would be legal if ungrounded. If this is the case, the first breaker in each string should be a GFCI, and pushing the test button on it should kill everything downstream. If this is the case, they're supposed to be clearly labeled both GFCI PROTECTED and UNGROUNDED. If someone simply replaced the old 2-prong with 3-pring to avoid using adapters without doing anything else, it's illegal as gently caress. The hazard is that if an appliance shorts out, case will remain energized but it won't trip the breaker, and can lead to shocks and possibly electrocution.

Bobulus
Jan 28, 2007

The only gfci outlets (IE, those with test buttons) I can find are in the kitchen, which is on a different circuit than the bedrooms I'm testing this in. I was assuming that the 3-prong ungrounded stuff was just grandfathered in at some point, it being a very old house, (especially since the remodeled room appears to have been done correctly), but if it is indeed impossible for them have done this legally, it gives me a lot more ammunition to get them to fix it.

This is going to be a huge hassle, though, I can just tell.

Motronic
Nov 6, 2009

Bobulus posted:

I was assuming that the 3-prong ungrounded stuff was just grandfathered in at some point, it being a very old house

Putting in a 3 prong outlet without a ground has never been OK (GFCI exception to that already noted), therefore it can't be "grandfathered".

The other place to check for GFCI is the breaker box. They COULD be on GFCI breakers.

grover
Jan 23, 2002

PEW PEW PEW
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:
:circlefap::circlefap::circlefap:

Bobulus posted:

The only gfci outlets (IE, those with test buttons) I can find are in the kitchen, which is on a different circuit than the bedrooms I'm testing this in. I was assuming that the 3-prong ungrounded stuff was just grandfathered in at some point, it being a very old house, (especially since the remodeled room appears to have been done correctly), but if it is indeed impossible for them have done this legally, it gives me a lot more ammunition to get them to fix it.

This is going to be a huge hassle, though, I can just tell.
2nding Motronic- that poo poo was never legal and is in no way grandfathered. Better to go through the hassle than get electrocuted. Someone did some criminally negligent work by the sounds of it.

ToxicFrog
Apr 26, 2008


grover posted:

Yes, that cable and breaker are both damaged. Replace the breaker for sure (they're cheap) and cut the wire back past where the insulation is visibly damaged before reconnecting. If it's #14 or larger, it's properly sized. I suspect the breaker lug was not properly tightened, as loose connectors can cause arcing (which was likely the crackling you heard) which cause heating and damage. Tightening lugs like this is actually supposed to be done on a regular basis as they can loosen up through time; pros will use thermal cameras to check for tightness as loose lugs show up as hot spots. In this case it probably just wasn't tightened right when it was installed.

Turn power off to the whole panel and give that wire a tug- if it comes out, that was for sure your problem. I would torque down every other bolt in the panel at the same time.

Awesome, thank you.

quote:

A loose neutral or ground is likely the cause of the 40V readings- readings like that are often phantom voltages due to poor connections. Probably the ground in this cases as you'd likely have experienced issues if the neutral was loose. Check all the ground connections in all the boxes in that circuit if you can.

We already did a visual inspection and nothing is obviously wrong, hence the conclusion that the problem is between the first outlet box and the breaker box - but I don't think we actually checked the tightness of the connections. I'll do that when we have the house powered down to replace the breaker. It'd be nice if we can fix this just by tightening the ground connections in one of the wall sockets rather than disassembling the entire wall.

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Dirty Beluga
Apr 17, 2007

Buy the ticket, take the ride
Fun Shoe
I'm having trouble understanding why ground is connected to neutral inside my electric panel.

I understand that ground is there to provide a path of least resistance in the event of a short, the current will travel through copper wire instead of you - this is why the chassis of an appliance / plumbing / etc... is connected to ground.

I also understand that the neutral wire is the normal "return" path for current.

What is confusing me is, if the neutral and ground are connected together in the panel, doesn't it mean that electricity could back-feed up the ground line to the chassis of an appliance / plumbing/ etc? everything goes to the same bus bar. it seems like with this wiring both the ground and the neutral are the same thing.

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