Electricity in U.S.A. households (and not only there)

[Electronic M]

Originally Posted by old_tv_nut

A stated above, I have two independent HVAC units, one for upstairs and one for down. They are both installed in the attic, and use gas for heating. The good thing is that the house can be made bearable by one while the other is down for repair. The bad thing is that the peak demand when both ACs randomly run at the same time disqualifies me for limited demand rates. Even though demand is recorded by the electric meter, this info was not accessible to first line customer service - they had to refer me to the engineering department to call me back a few days later and tell me the peak demand on my account and determine that switching to demand-limited service might actually cost me more overall with penalties for exceeding the limit.

I have a 200 amp panel with nine open slots out of 40 total.

Since we have buried utilities here, I have no idea what the transformer ratings or homes per transformer are.

If both units are in the attic you could probably implement some really simple relay logic to lock out AC on one unit when it is on on the other...

[old_tv_nut]

Originally Posted by Electronic M

If both units are in the attic you could probably implement some really simple relay logic to lock out AC on one unit when it is on on the other...

True, but first I'd have to determine if max 50% duty cycle is sufficient in the summer. Plus, this would be creating a non-standard setup that would have to be explained to confused repair techs, since I no longer go attic crawling to work on this stuff.

[pgnl]

A bit late but while you’re talking about mains electricity.

What you may not know is that the UK mains is wired differently from most countries. Its why we have much larger plugs.

Basically the mains outlets in a house are wired using in a loop from and back to the breaker board using I think 20amp cable, so potentially each outlet could supply 40 amps. Normally one ring per floor. Certain spurs from the ring are allowed. Cookers and electric showers have a separate (I think 30 amp) circuit. Sounds unsafe? Well of course we have breakers on each circuit - but there is also a fuse (either 2 amp, 5 amp or 13 amp) in every plug, so if the device goes open circuit its cable wont melt and cause a fire. The idea was to reduce copper at a time of shortage - it has been used (i might add very safely) since 1947. Thats when the square pin fused plug was first used and also the reason why the EU abandoned plans for a standardised plug design, as our houses would need rewiring…

Prior to 1947, houses were wired the same way as everywhere else but had three different plug sizes. 2 amp, 5amp (like the current plug used in India) and 15 amp (like the old south african plug. Some were two pin some were three pin. My grandparents house had a variety of sockets. Usually the lighting was on different circuit because at some point before ww2 electricity was more expensive for lighting than for heating.

The UK 13 amp square pin plug may be large, but it was designed to be safe, all sockets are shuttered and normally switched. There is loads on the web about its safety features.

Normal 13 amp sockets werent allowed in the bathroom, but are now as long they are a certain distance away from a sink or bath/shower. There is a special two pin isolated bathroom socket permitted for electric toothbrushes etc. lighting switch is usually a pull cord or a switch outside the room. Sometimes I think they need to bring those requirements into the 21st century?

Hope you find this interesting…

Patrick
Ps I thought you might like to see my breaker board, much simpler than in other countries I think. Latest UK requirement is for the box to be metal, mine is plastic…

[Telecolor 3007]

In Romania we had all kind of voltages, types of electricity (a.c. and d.c.), two phaes current, even different frequncyes (42 and 50 Hz. (Cy.) ). But the sockets, I think they where common - German standard.
As for today's fuses, I think the case can be from plastic. I do like plastic more because is an better insulator. In the past, they used metal, but also wood and marble and plastic or P.V.C.
Who haves 3 phase current at home?