Correcting incoming utility power for a household

I'm not particularly clued up with regards to electrical systems etc, so please forgive me as I'm pretty sure I'm not going to be asking or phrasing this correctly.

The problem that I have is that the incoming utility power into my house is .. k@k. The other night the voltage dropped down to 211V (according to one of my many UPSs) - this kept causing the mains to trip out. There are often brief dips, lights flickering etc. This is seriously annoying me, as I'm sure this is not doing my equipment much good.

Is there any way that some or other device could be attached somewhere to the incoming power feed that could rectify the supply so that there is a constant voltage? What would this device be called - and how much would I be looking at approx? I'm guessing something like this wouldn't be cheap.


TIA.

Your mains shouldn't continously trip at 211V hey. It should be stable across a range of voltages - 200-240. But yes, 211V is a little crappy.

You can get yourself an online UPS. In layman's terms, this takes the input power, converts it to 12VDC -> battery -> up to 220V, then it powers your devices. Only issue is, it costs a heck of a lot of moola.

Yip, a UPS for your whole house would be expensive. Just put one on your PC and other sensitive devices like tv or hifi. Else it shouldn't really be a problem, nor should it (211V) cause your power to trip.
211V aint that bad (220-211/220 = 4%error), SA uses 220V ac usually, but alse 240 or so depending on your wherabouts.

IIRC 210VAC was normal in the East Rand area back in the 1980s, it certainly shouldn't cause earth leakage trips.

Earth leakage units exhibit this behaviour as they age and should be replaced if it is tripping for no reason.

FrancTheTank said:

Yip, a UPS for your whole house would be expensive. Just put one on your PC and other sensitive devices like tv or hifi. Else it shouldn't really be a problem, nor should it (211V) cause your power to trip.
211V aint that bad (220-211/220 = 4%error), SA uses 220V ac usually, but alse 240 or so depending on your wherabouts.

Click to expand...

Frankc's right. The SANS standards dictate a maximum loss from source to load of 10% is allowed. This means from the supply transformer at your substation down the road ... right to your outlet points (plugs) in your house, you may only have a drop of 21Volts on a 220V system. However a lot of transformers run on a 240V system, which means your plug has to have a minimum of 216vac on it.

Your mains won't trip out from undervoltage, but rather from overcurrent (which is actually a derivative of under voltage) in the event of too many appliances etc drawing power. The usual suspects here are motors inside: fridges , tumble dryers, washing machines & microwaves with surge currents that can spike quite badly for 1-4 seconds. If your supply cable isn't properly rated (not for current, but rather volt drop across the distance) then this can easily upset your ups.

Ok... when the mains kept tripping, the one UPS showed that it was receiving 211V.. this is fairly low compared to what I've seen, so I assumed that it was the cause of the constant tripping, because I could find no other reason for it. I switched off all unnecessary lights, unplugged all sorts of other things around the house to reduce load, but still the mains kept tripping.
I then switched off the three 'plug' circuits that the board has, and then switched mains back on. I then switched each plug circuit back on, until I had figured out that the plug circuit that supplies my office/home theatre setup was causing the tripping. I switched off all my PC devices, including the UPS's, so there was nothing drawing power in my office. leaving only the TV equipment drawing power.. that being, PS3, Receiver, Tivo, DSTV decoder and the flat panel LCD.. and the xbox power brick, although the xbox itself was off. That circuit STILL caused the mains to trip.
The whole TV unit is supplied by a dual outlet plug socket, so I switched off both sockets, and no more trips. I then switched on the one plug... no trip. Switched on the other one, no trip.
Then 5 minutes later, the mains tripped again. Eventually I gave up, switched off all the TV stuff, put my computers back on and played some games instead.
I think my office was an addon to the house, and they simply extended power from the lounge plug circuit to give it power. Now I'm drawing one heck of a lot of power down that circuit, so it bothers me a bit.

I do know that there were power troubles in the area that night, as it was quite cold, and my in-laws who live about 2k's away on the other side of the highway were without power. Our own power went out at around 04h15 and only came back around 11am.

Power has been stable since then... but the incoming power still worries me in that it never seems 'stable', and it annoys me that I hear my UPS's clicking every now and then when voltage seems to drop a bit.