You could do that with a meter but unless you know which appliance is running on that phase it isn’t going to help you. You can use a meter to help fault find though by seeing which phase is overloading then educated guess as to which appliance is likely to be the cause and test that.
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Yes exactly, hence the words harmonisation and nominal voltage throughout the legislation.
With the range limits set in the “harmonisation” at +10% to -6%, the reality is nothing has changed.
The great EU fudge machine at its best.
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Dear bruss and Naim Forum members. I am a retired electrician amongst other employment positions. This is the device I use when measuring currents in cable, and it also has a Data Hold mode. Though also, be aware that it also has an auto turn-off ability as well to conserve batteries. I do not wish for you to get inside your switchboard (fuze box), though, if it looks safe enough and you only use one hand to measure. Never insert two hands into a switchboard; this device may help determine current loadings between phases.
Kind regards,
Mitch in Oz.
I have a 3-phase supply, my Naim kit is on one of those phases but I’ve no idea which.
Like many Naim users, my kit is connected to a dedicated circuit with circuit breaker feeding only the Naim kit.
Other devices / circuits likely use the same phase but I’ve no idea what.
I still get humming on occasions from the toroidal transformers but I live in a remote rural area and am not likely to ever get a constant, clean incoming mains supply 
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For the avoidance of doubt I am not suggesting that anyone other than a qualified electrician should attempt to balance a three phase supply.
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We have a three phase supply here, but I think that was mainly due to agricultural needs. Only issues we have had with it are the exposed copper cables that run for about half a mile from the road down the edge of a wood along the side of one of the fields to the house. Whenever the wind gets up the tree branches move the wires around and they can touch which causes all kinds of fun. Usually it’s nothing worse than a transformer trip or short power outage, but last Summer a branch took out the earth cable at same time as touching the other wires together, which resulted in them welding themselves together in a few places and feeding the house with over 400 volts - without the earth wire connection the transformer did not trip out! Hopefully not an issue these days with a modern installation as any new cabling would not be exposed like this (these cables must be 60+ years old by now), although the UK Power Networks are reluctant to change them for newer and safer sheathed cabling…
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Dear bruss,
I apologise for the confusion. I would not ask anyone to balance phases. However, the device I have mentioned would give an accurate, current loading of each phase. This would provide evidence if you needed to balance phases. Here in Oz you have to be a very special load to the consumer mains to have three phases connected to your property. Three phase connection is mainly for commercial, industrial and farming and even farming can be just two phase. Very rare for domestic.
Warm regards,
Mitch in Oz.
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Thats interesting ( and worrying). When they repaired did they correct the earth situation with an additional earth to your house and to the transformer?
The house earth was fine. IIRC it was one of the 4 exposed wires back to the transformer that would cause the transformer to trip. It was this wire that broke as the other cables touched and welded themselves together, thus giving us a much higher voltage than usual!
According to the UK Power Networks guys who came out to rectify things, it’s quite common with the old exposed copper cables - so much so that they have a special pole with an attachment on it that they run up and down the cables to try to un-weld them when it happens. In one particular spot with ours the cables were so solidly welded that they thought they might need to replace the wires entirely. However, with about 10 minutes of really running the pole along and hitting the weld hard over and over it finally parted.
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We have solar, batteries, heat pump and 7kW EV charging. We had 100A single phase rating but the DNO took the opportunity to restrict us down to 80A. The installer was told to current limit the Zappi to restrict the total load on the grid. I’m not aware of any power reductions. The peak scenario is during cheap rate when batteries, ASHP, EV and a few appliances are running. Our solar inverter is only 5kW, which mostly copes with the daytime demand.
In the UK we pay for grid connection upgrades. I can only export at 3.68kW which annoys me.
Phil
Filipe, that’s very similar to us: second battery going in next week, but no worries about the 100A being downgraded. However, we have been offered a free 3 phase connection (we will have to pay for new boards, though).
Our electrician is considering putting the batteries, heat pump and EV on one phase dedicated to cheap overnight rates.
I am intrigued as to whether anyone loads their phrases in a particular way such that the system has the cleanest feed?
In the UK you will need Surge Protection on each CU (£100 each). I suppose if I were to have a 20kW 3 phase EV charger I would need it. We can charge ours overnight though.
My current feeling is that I will switch to Octopus Agile from Flux. The Agile rates are cheaper than Flux. My main Flux benefit is the near to Standard rate for exports between 4-7pm.
Most batteries aren’t as efficient as the blurb might have you believe. My SolarEdge is barely 80% allowing for inverter overheads as measured by the net meter. Decent amounts of solar without grid charging the battery give better figures. I’m weighing up misleading advertising.
Phil
We are using Tesla Powerwall2, and the first one has been nothing short of brilliant; pretty much spot on even after 18mths. It sits outside, so does lose a percent on very cold nights. The new ones have come down in price hugely partly due to the advent of the up and coming PW3.
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I seem to remember that in the thread “The Listening Room Reality” Thomas posted a wiring diagram which implied (or from which I inferred) that he had three phase and was planning on separating the phases to use a specific one for audio. However, i) that thread is very long and on a quick look just now I couldn’t see the diagram and ii) Thomas stopped posting before the listening room was finished, so this wouldn’t give any results of the separated phases.
It struck a chord with me at the time because I have domestic three phase in the UK (plus batteries, solar, and a 22kW car charger etc).
Ah, another 3 phaser (apologies Trekkies!). Do you notice any acoustic benefits?
I started my Naim journey in this house with its existing 3-phase supply, so I don’t have a comparative bench mark.
I don’t have a dedicated hifi supply, nor have I taken any action to separate the phases. To my ears though, it sounds phenomenal. I had an upgrade today to a 222 and that’s taken it up yet another level. Amazing. But like I say, that’s a purely subjective view with no real comparative data when it comes to single vs 3 phase.
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As my electrician pointed out, you can have different things in your home on different phases, split the earth, try and do all sorts of things to isolate things in the home from each other, but you cannot isolate any phase from your neighbours connected to the same substation. They all branch off the same 1-3 phases (depending on your country).
I find the most effective way is if you have a phase coming in that you dedicate for the hifi, with it’s own CU, give it it’s own dedicated earth (and therefore neutral) too.
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Thank you F-Z, that is really interesting. So, you can dedicate a phase to the Hifi, but that earth (and neutral) plus separate circuit from parallel consumer unit, trumps phase?
I can’t answer that but one you have control over and the other you don’t
So in my country it is dual phase. Main CU gets dual phase and it’s mandatory TT earth to feed neutral and safety earth. The hifi CU gets a dovetail off one phase but it’s own dedicated TT earth.
But even if I had three phase I might have been able to supply one that wasn’t elsewhere in the house but it would still have been shared with every other house on the street.
Stable unpolluted earth can at least be supplied and shared with nothing.
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Incontrovertible logic and sense, as always!