Minimal Residential Electric Service

[ronswelters2]

We have what appears to be the standard low level service on our small Bangkok shophouse, 15-45 amps. Is the 45 amps the limit on this service?

There is a 63 amp rated Safe T Cut device that I take to be a combined breaker tripped by excess current (64 amps?) and also by leakage showing up as unequal current between hot and neutral.

What is likely to happen with an overload of say 50-60 amps? (Say from a water heater and a couple of aircons and say some kitchen stuff).

Does the meter blow, or is there typically some fuse on the company side of the circuit? I'm assuming a 63 amp breaker trips at 63 amps, but I'm no expert.

Swelters.

By the way, the Thaivisa stuff on electricity is invaluable, I jus didn't see the answer to this elementary question.

[Crossy]

Hi Ron.

The maximum continuous load on your meter is 45A, however meters are very robust so even a fairly significant overload won't do any damage.

It depends on the actual device characteristics, but the 63A breaker will open in about 5 minutes at 50% overload (not 64A) so it won't even notice your 50-60A load.

IMHO you'll be just fine, you're unlikely to have all the loads on at once anyway

That said you should do a maximum-demand calculation to be sure.

[david96]

If your meter size is 45A you most likely have 50A consumers mains, but one should verify this. A service fuse or protective device may not be installed. Your mains will accept short sustained overloads providing there is no undue temp rise. If your consumers mains are larger 63A will provide the protection you require.

You should carry out an MD calculation or calculate your MD by assessment, ie: the max sustained load over any 15minute period. the second option is the best.

[ronswelters2]

Thank you both, gentlemen, this is a big help.

Ron

[powderpuff]

You're lucky. Just a few short years ago "standard" meters were 5/15 amp.