Downgrading 3 phase supply

[chrisc]

I have 3-phase and solar

I disconnected all the lights and some plugs that were spread over 2 phases and created a 4th power source. To be safe I fitted a 4-pole main switch

Had it approved by an electrician and he issued a COC. That was in 2015

The whole system broke even in March this year

Try not to make it complicated. The 3-phase pre-paid meter works just fine

 

[Lct00]

Krieg I am going to run all my plugs and lights through my inverter... this is not gonna be for emergency but more like a semi off grid. Its just if i have all my plugs/lights on 1 phase but only my geyser and oven on the other phases it will creat a huge power imbalance so that was my reason behind making it single phase then I wont have to worry about moving circuits around in my db

 

[krieg]

Krieg I am going to run all my plugs and lights through my inverter... this is not gonna be for emergency but more like a semi off grid. Its just if i have all my plugs/lights on 1 phase but only my geyser and oven on the other phases it will creat a huge power imbalance so that was my reason behind making it single phase then I wont have to worry about moving circuits around in my db

If you have the cash to convert it in one go and you don't need extra capacity in the future then go for it.

 

[Speedster]

If you connect all the incoming cables together you will have 450 volts which is useless. If you just use one cable everything will be unbalanced.

And a lovely explosion to boot

 

[Speedster]

You pay more for a 3 phase supply. So downgrade to a 1 phase supply for the saving

Same price

 

[Geoff.D]

If i understand this correctly you want to disconnect 2 phases on the incoming side of the breakers.
Then basically bridge the incoming side and connect the 3 wires feeding our DB into this bridged breaker ?
Is this it ?
If so your ESCOM feed will be unbalanced and have an effect or your pf. Witch in turn will lead to a more inefficient system and therefore more expensive.

Never mind the fact that he will piss off Eskom and they will make themselves very unpopular. Do it correctly and apply to Eskom to convert to a single-phase power feed, which they may not be prepared to do anyway, which will mean he needs to get a professional in to help work out how he can maintain a reasonable phase balance and still implement a single backup on one phase only.

 

[Geoff.D]

Not sure where you are but here in Cape Town the municipality does that and you pay for it.

The first sensible post you have made on this thread.

 

[Speedster]

Just connect your whole db to a single phase and leave the other two unused. Why go through the schlep of terminating the connections?

 

[Magnum]

I see, is that because they are 120 deg out of phase or is there another reason ?

No, Because Star gives you 220V. Delta 380v.

 

[Geoff.D]

No, Because Star gives you 220V. Delta 380v.

Getting far too complicated. You are overthinking the whole issue.

 

[Geoff.D]

Just connect your whole db to a single phase and leave the other two unused. Why go through the schlep of terminating the connections?

You might get away with it in Municipal power systems but not with Eskom - they take phase balancing quite seriously. Maybe I should add they used to take it seriously and make a big deal out of it..

 

[Magnum]

Getting far too complicated. You are overthinking the whole issue.

Well I could list the Whole text book on 3 Phase. many here would jump ship.

 

[Speedster]

You might get away with it in Municipal power systems but not with Eskom - they take phase balancing quite seriously.

That's a good point. Has OP mentioned who his power provider is?

 

[Crush]

First of all, surely it's illegal to touch or tamper with the outside meter. I know that for CoJ, the outside belongs to City Power and you aren't allowed to do your own work on it.

Secondly, If you're going solar, you are already spending in excess of R100k if you're doing its remotely nicely. The extra cost of a 3-phase inverter is R10k-R12k I think. So why not just do that? How much would it cost you to apply and do the conversion to single phase?

At the end of the day, I think you're squabbling over R5k or less?

 

[Geoff.D]

The trouble farmers have on single-wire, earth-return distribution systems can keep you spell bound for hours!

There, the "balancing" between the two-phase feeds to farms becomes quite a big issue. Eskom does not bother - they just trip the feed and then you have to call them out to reset the feed and it may trip a whole group of farms and then all your neighbours are really pissed off because you have failed to ensure a reasonable between the two pseudo phases.

 

[Speedster]

First of all, surely it's illegal to touch or tamper with the outside meter. I know that for CoJ, the outside belongs to City Power and you aren't allowed to do your own work on it.

Secondly, If you're going solar, you are already spending in excess of R100k if you're doing its remotely nicely. The extra cost of a 3-phase inverter is R10k-R12k I think. So why not just do that? How much would it cost you to apply and do the conversion to single phase?

At the end of the day, I think you're squabbling over R5k or less?

Why not, as I said earlier, connect the inverter and db up to one phase and leave the other two unused?

 

[Geoff.D]

First of all, surely it's illegal to touch or tamper with the outside meter. I know that for CoJ, the outside belongs to City Power and you aren't allowed to do your own work on it.

Secondly, If you're going solar, you are already spending in excess of R100k if you're doing its remotely nicely. The extra cost of a 3-phase inverter is R10k-R12k I think. So why not just do that? How much would it cost you to apply and do the conversion to single phase?

At the end of the day, I think you're squabbling over R5k or less?

Exactly. Taking silly shortcuts in this game is absolutely pointless and just inviting trouble - Murphy is on the lookout for situations like this.

 

[Crush]

Why not, as I said earlier, connect the inverter and db up to one phase and leave the other two unused?

I'm actually not sure exactly why, but electricians are quite hesitant to do this. Maybe only if you're pulling lights, TV and small loads, but definitely not for entire DB's.

I understand my single phase DB well enough but I haven't read up on 3-phase and definitely don't know what phase balancing entails and how it works inside a single household.

 

[Geoff.D]

At one stage, Roodepoort used to provide 3-phase power to some residential areas. The council used to "inspect" your distribution and demand changes if they decided the phase balance was not within limits. There was a time when the plan was to implement a PF charge if you failed to comply.

 

[upup]

So I also want to downgrade to single phase - purely because I don't need it - house has got 3 Phase because it had a ducted aircon system which I discontinued years ago and went with splits.
I know I pay a premium for 3 phase so want to downgrade to single phase.
Can an electrician do this, or do I have to get the municipality to do it ?

I got 3 phase too, but does not pay more for it per month. 3 phase electric motors are cheaper if you need a big diy thing.