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Thanks for the clarification, PRR. It looks like the US system is quite different from the one in UK (and I suspect the Australian system is a lot closer to the UK's than the US one). On most new UK residential installations the system earth (ground) is bonded to the incoming neutral conductor at the main fuse box where the supply enters the premises. There is only one phase in residential systems, so the neutral does carry current (but the local system earth conductors do not unless there's a fault). We also have fused plugs for appliances, so manufacturers are allowed to use light cables with a low current fuse in the plug. Obviously live and neutral have to be the right way round in this scenario to make sure the plug fuse is always on the live side, hence my earlier comment about keeping a fire extinguisher handy if L and N are reversed.
 
The function of a "ground fault" breaker does not rely on a ground wire. At least not in US practice: we sense the DIFFERENCE between the two current-carrying conductors. Some write-ups of UK ELCBs suggest otherwise, that they fail to detect fault current which does not flow through the ground rod.
RCDs (Residual Current Device, used to be called ELCB) in the UK also work on the current-difference principle. There are still some that rely on an earth conductor current in old installations but they are gradually being replaced.
 
> US system is quite different from the one in UK

It is and it isn't.

The US electrified before good insulation. The thinking was that if voltage was closer to 100V, this would be safe. And that a couple thousand watts for lighting was all most houses needed.And a LOT of houses were wired this way. I have a 1910 book explaining how electric companies can promote house-wiring by sending salemen door-door and sub-contracting electricians at a sweet rate for a standard 13-lamp job, spread out over the first year of electric bills.

The UK was less aggressive about electrification. Also more local standards and specials. When electricity was ready to grow big, the Depression damped spending, and then the War stopped all new domestic upgrades and destroyed many existing electric installations.

I gather that the UK did a major post-war re-think. That most UK electric gear was standardized around 1950 with benefit of hindsight and a massive re-building market. The 230V voltage, ring-circuit and fused plugs saves a lot of copper and labor. In the US I run a a separate cable for about every room (2 rooms one some cables, 2 cables to one room). The generally single-pole main box is elegant; "2-phase" invites mistakes. I'd love to do that here; but small 230V lamps and appliances are rare, US wall-outlets invite finger contact, and the ring-main is an utterly alien concept to my Inspector (yeah, we got one recently) and to anybody who comes after me.
 
Is one of the pieces of equipment "double-insulated" and the other a grounded chassis?
Double insulated equipment "GND" will float since it is not referenced to chassis earth and you can get approx half the AC mains voltage difference on it wrt chassis earth.
 
Another reason to leave it to a professional is that there can be cloth insulated wire in there.  That stuff is very tough to deal with!  You can fix or replace an outlet, test it GOOD, but it will pop when you put real current through it.
Have your landlord make the wiring proper.  Sometimes it takes a 50-50 split or other incentive (birthday song for their kid, etc.) but they should do it.
Mike
 
mulletchuck said:
Have your landlord make the wiring proper

I'll see the landlord today, so i'll mention it.  see what he says.

Look into the NYC renters ordinances and you will find they have to provide a safe place for the rent you pay. I do control work, and hep some of my family members with house wiring issues but hadn't dealt much with that old of building or wire.

IMO I would force the issue to the landlord for them to correct. If you correct it your taking the responsibility if there is something wrong, or a fire afterwards.

The NEC is starting to go toward a NWC in the 2008 edition, so it's adopting more of a word approach.
 
kazper, i'm not in an old building.    but my bedroom used to be the dining room.    I searched the building code and found nothing about ensuring power outlets are grounded, only that lighting must be provided around the building.
 
I'd simply start by asking them to fix the outlets, tell them you checked them with a tester and found the issues.

Look at your rental agreement and inform them how it says there, and keep track of everything.

It's not that big of a deal to fix if it's a newer place.

I could go on but it's not worth it.

Where I live and because I know alot of electricians I'm blown away by the fact they charge people $50-80 to change a single outlet.
 
> I searched the building code and found nothing about ensuring power outlets are grounded

The major US building codes leave the electrical to the NEC Code.

BTW, neither BOCA/IBC nor NEC has any legal standing; that's up to the town/city. But the majority of towns formally adopt one of the building codes and an electric code (the NEC is the only widespread electric in the US) with little or no local modification. (NYC, Chicago, Boston, and I hear Austin have local details.)

GroundED and GroundING crept into the NEC over a 50 year span. Even though 250 is about grounds, the full details are spread all over the book.

For recent legacy existing work (built well past 1972), there must be two 20A grounded circuits in kitchen/pantry. Two so that you can plug in a hi-power toaster and a hi-power Mr Coffee without overload. Grounded because before double-insulation or GFIs, grounding was the best bet around water pipes. When GFI costs came down (early 1980s?) then any outlet within reach of plumbing (specific distances in code) shall be GFI.

I don't have an NEC here. I do know that "ALL" recent construction that I have seen is 3-pin outlets everywhere (with odd exceptions like clocks and other dedicated quasi-permanent outlets). And a 3-pin outlet "must" have an effective groundING wire back to the fusebox (or read a special Exemption using GFI to provide life-safety without a useful audio ground). I "assumed" 3-pins are generally required, but I can not cite chapter and verse.

More recent changes want TR (hairpin proof) outlets many places, and Arc-breakers in bedrooms. Neither change affects your studio.

When I had my new-room wiring final-inspected, the inspector had a 3-light tester to sample a majority of outlets for the "OK" indication. I'd think that failing the 3-light test would be a legitimate safety concern.

The Code does not prescribe Good Audio. And landlord or inspector may shrug-off some faults where they do not see a safety issue (and arguing only makes things tougher). For small studios, find one preferably grounded outlet somewhere, safely run a fat 3-pin cable to the studio, and get a many-outlet power strip to plug all your goodies into. As long as they all reference each other, there should be no significant voltages between panels. If they also all reference building ground, there should be no voltage to radiator or sink, and lower EMI from building wiring ambient field.

Codes upon codes. The NFPA (fire) code prohibits power-strips, daisy-chaining, and permanent extension cords. This cost me $4,000. I had 3 wall-outlets in my audio/computer workshop, so it was ALL extension cords and powerstrip into powerstrip. The upshot was I got three new circuits and nine new 4-hole outlet boxes, and it really did work better. But if you are not prepared to invest, then be sure ALL your hay-wire is "temporary", and keep it looking like you just wired-up this morning and will un-plug before you go to bed.
 
1990 repairing a Pultec EQP-1.  Probing with an oscilloscope on a powered up unit.  Watching the probe tip, my pinky finger touched B+.  Should I say that got my attention!  My right arm was tingly and numb for about an hour.  Got the unit fixed finally though.

Regards,
Jeff

Ooops, this was supposed to be in CJ's thread!
 
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