3 Phase Power

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greggpb

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I know it seems stupid,

Do you need a 3 phase generator if you have 3 phase power at home ?
 
The only appliance that is wired for 3-phase power in a normal household is an electric stove. You would never (seriously) run that off a generator, so everything else would work fine.

You would also never plug a a generator directly into the distribution board, so when its done properly, a qualified electrician would know what to do...
 
Well, phases should be balanced. So a generator just one one phase (and putting your load only on one phase) means your phases won't be balanced anymore. Obviously depends on the load...
 
savage said:
Well, phases should be balanced. So a generator just one one phase (and putting your load only on one phase) means your phases won't be balanced anymore. Obviously depends on the load...
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Thanks so much guys, building our house in phases so we went 3 phases but think we are only using one at the moment, so as a quick fix I should be able to get a 1 phase generator.
 
Gordon_R said:
The only appliance that is wired for 3-phase power in a normal household is an electric stove. You would never (seriously) run that off a generator, so everything else would work fine.

You would also never plug a a generator directly into the distribution board, so when its done properly, a qualified electrician would know what to do...
Click to expand...
THanks mate, thankfully GAs Stove
 
greggpb said:
Thanks so much guys, building our house in phases so we went 3 phases but think we are only using one at the moment, so as a quick fix I should be able to get a 1 phase generator.
Click to expand...

If you got a 3-phase supply, that means you are using all 3 phases. What you need to do is get the council to change your 3 phase to a single phase.
 
Only stick with three phase if you actually have a good reason to do so, otherwise you will keep having extra costs for it at every turn when it is unnecessary.
 
If your house is supplied by 3 phase you can still use a single phase generator by simply bridging the 3 live wires. Am I correct at saying this?

Since everything in the house is single phase even the poolpump this means that if you get 3 phase supply from the municipality or eskom they simply wired the house to split the load over the 3 live wires. It does not mean your appliances are suddenly 3 phase.

Also I stand to be corrected but if you have 3 phase power you must be on postpaid billing and receive a bill where they measured the consumption on all 3 live wires?

Also I don't think it is very important to split the load equally across the phases unless you got sensitive 3 phase ewuipment running. I stand to be correct because I'm no expert.
 
HavocXphere said:
Don't see why a house would need 3 phase at all tbh.
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There is a physical limit to how much current you can draw through a single phase power supply (typically 60-80 amps). A large residence with electric stove, geyser, tumble drier, and room heaters would easily exceed this limit at times.

BTW: Tripping the mains power can be a great inconvenience (especially if you have to phone the council to get re-connected!?)
 
I have 3 phase at home. I'm on prepaid. The meter measures the power of all the phases independently. AFAIK, the load doesn't have to be balanced - all my loads are single phase. I could run everything off one phase if I wanted.

The advantage of 3 phase, is that you have more power available - 3 x 60 A = ~ 40kVA., and you can run 3 phase equipment. If you have lots of aircons, pool heater, jacuzzi, etc, then it is handy.

You can't bridge/join the phases together!
 
greg_SA said:
I have 3 phase at home. I'm on prepaid. The meter measures the power of all the phases independently. AFAIK, the load doesn't have to be balanced - all my loads are single phase. I could run everything off one phase if I wanted.
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6.1.1 In a multiphase installation, the circuits shall be so arranged that the total load is, as nearly as is practicable, balanced between the phases of the supply.

I really, really, don't suck all these things I say out of my thumb. Really, I promise.

And yes, as others have said, you can get max 60A on a single phase. If you need more than 60A (for whatever reason), a three phase installation is a must. I've personally worked in residential houses with elevators and escalators and stuff in them :D
 
The Eskom guy told me I have polyphase. Anyone know what that is?
 
savage said:
6.1.1 In a multiphase installation, the circuits shall be so arranged that the total load is, as nearly as is practicable, balanced between the phases of the supply.

I really, really, don't suck all these things I say out of my thumb. Really, I promise.

And yes, as others have said, you can get max 60A on a single phase. If you need more than 60A (for whatever reason), a three phase installation is a must. I've personally worked in residential houses with elevators and escalators and stuff in them :D
Click to expand...

I never said anything about the regulations - was talking about what happens in practice... so I'm not disagreeing with you.

I have my geyser and oven on one phase... So in the evening, I am drawing almost everything from that phase, and almost nothing from the others. So my understanding is that it is not a technical requirement for your house... is is just what is ideal from a distribution point of view?

The fact that the 3 phases are balanced higher up stream (taking many houses together into account) is just random...
 
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