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From: Rick on 28 Apr 2005 11:11 Hi Group, I am wiring a room in my basement. It is a new room. I have purchased 2 books on home wiring and I am confident about doing the work myself. I have 4 plug outlets, one light switch, two light ceiling outlets. I am 'daisy chaining' these together to go on the same circuit. As such, I am pig tailing the wires to connect to the actual outlet devices. My question is about the grounding. To save a few dollars, I purchased these metal cases for the outlets that seem to be all I would need. Except, when I look at the existing ones that were put in when the house was built, they are a bit different, namely, there are two screws in the case for the ground wires. Since I have 2 wires passing through for the daisy chaining, I also have two ground wires. So, finally, the question: Is it OK to put two ground wires on the same screw? Or, is the double screw cases really made for a reason? IE. Do I need to buy a new metal case to provide appropriate grounding. I would think not, since even with the double screws both grounds are for all intents and purposes connected to the same box? Anyhow, thought I would ask to be safe. Thanks for your time and resonses. Rick.
From: tlbs on 28 Apr 2005 11:59 Disclaimer: you need to check your local building codes to be absolutely sure. What I have seen (and done) time-and-time again is this: Connect the 2 ground wires together along with a 3rd short pigtail, all in a wire-nut. Connect the pigtail to the ground lug on the outlet or switch (or to the box). I believe it is safer to connect the ground pigtail directly to the outlet or switch ground-lug. One other suggestion: if you can, don't connect all the outlets and the overhead light to the same circuit breaker. The load on the circuit breaker is not the issue -- the problem is, if that particular breaker goes bad you lose everything in that room simultaneously. If one or two outlets are on a different breaker, and a desk lamp or nightlight is plugged into those outlet, then you would still have some light/power in the room when the light breaker failed. This has happened to me (breaker failure -- overhead light only). I have observed the practice I described in several homes.
From: John Smith on 29 Apr 2005 04:07 "tlbs" <tlbs101(a)excite.com> wrote in message news:1114703967.278251.279020(a)g14g2000cwa.googlegroups.com... > Disclaimer: you need to check your local building codes to be > absolutely sure. > > What I have seen (and done) time-and-time again is this: Connect the 2 > ground wires together along with a 3rd short pigtail, all in a > wire-nut. Connect the pigtail to the ground lug on the outlet or > switch (or to the box). > > I believe it is safer to connect the ground pigtail directly to the > outlet or switch ground-lug. > > One other suggestion: if you can, don't connect all the outlets and > the overhead light to the same circuit breaker. The load on the > circuit breaker is not the issue -- the problem is, if that particular > breaker goes bad you lose everything in that room simultaneously. If > one or two outlets are on a different breaker, and a desk lamp or > nightlight is plugged into those outlet, then you would still have some > light/power in the room when the light breaker failed. > > This has happened to me (breaker failure -- overhead light only). I > have observed the practice I described in several homes. > As tibs says, put the plug outlets onto a separate breaker to the lights. Also, create a ring for the plug outlets, not just daisy-chain. (I.e. loop the end of the daisy-chain back to the breaker). Should give you (a) smaller wire requirement, thus a bit cheaper, and (b) a second path if something breaks in one leg.
From: Dr Engelbert Buxbaum on 7 May 2005 00:51 Rick wrote: > Hi Group, > > I am wiring a room in my basement. It is a new room. I have purchased 2 > books on home wiring and I am confident about doing the work myself. Frankly, I am not so sure. At least, have your work checked by somebody qualified. In most jurisdictions, you are actually required to do that by law. > I > have 4 plug outlets, one light switch, two light ceiling outlets. I am > 'daisy chaining' these together to go on the same circuit. As such, I > am pig tailing the wires to connect to the actual outlet devices. My > question is about the grounding. To save a few dollars, I purchased > these metal cases for the outlets that seem to be all I would need. > Except, when I look at the existing ones that were put in when the > house was built, they are a bit different, namely, there are two screws > in the case for the ground wires. Normally, you have 3 wires in house installation: live (usually brown), neutral (usually blue) and protective earth (PE, usually green/yellow bicolour). Some heavy duty equipment may have 3 different live wires (brown, grey and black) carrying the voltage with different phase, giving a total of 5 wires. This includes kitchen ovens, air conditioning, flow through water heaters and the like. Only in very old installations are neutral and PE connected at the outlet ("nulling"), this type of wiring has been forbidden for a long time, because it prevents the use of residual current devices (RCDs). By the way, have you included a RCD in your fuse box? If not, reconsider because these thingies are real life savers if things go wrong. 30 mA is the prefered size for house installation.
From: Jamie on 7 May 2005 14:18
Dr Engelbert Buxbaum wrote: > Rick wrote: > > >>Hi Group, >> >>I am wiring a room in my basement. It is a new room. I have purchased 2 >>books on home wiring and I am confident about doing the work myself. > > > Frankly, I am not so sure. At least, have your work checked by somebody > qualified. In most jurisdictions, you are actually required to do that > by law. > > >>I >>have 4 plug outlets, one light switch, two light ceiling outlets. I am >>'daisy chaining' these together to go on the same circuit. As such, I >>am pig tailing the wires to connect to the actual outlet devices. My >>question is about the grounding. To save a few dollars, I purchased >>these metal cases for the outlets that seem to be all I would need. >>Except, when I look at the existing ones that were put in when the >>house was built, they are a bit different, namely, there are two screws >>in the case for the ground wires. > > > Normally, you have 3 wires in house installation: live (usually brown), > neutral (usually blue) and protective earth (PE, usually green/yellow > bicolour). Some heavy duty equipment may have 3 different live wires > (brown, grey and black) carrying the voltage with different phase, > giving a total of 5 wires. This includes kitchen ovens, air > conditioning, flow through water heaters and the like. > > Only in very old installations are neutral and PE connected at the > outlet ("nulling"), this type of wiring has been forbidden for a long > time, because it prevents the use of residual current devices (RCDs). > > By the way, have you included a RCD in your fuse box? If not, reconsider > because these thingies are real life savers if things go wrong. 30 mA is > the prefered size for house installation. when wiring lighting and plugs, the 2 two are not to be on the same circuit. they need their own breakers. color codes normally are Black for HOT, white for Neutral and Green for earth Ground. the neutral and earth ground are to be connected in the breaker box on the ground bus bar, then an earth ground electrode and possibly a water pipe that is near by that has been conductive tested connected to the ground bus bar using no smaller than 10 #awg bar copper wire. this is the NEC codes the last time i looked. P.S. Remote fault breakers (GFI's) are also required in some localities. just thought i was spit in my 2 cents worth. |