3 phase is it worth getting?

[Agroshield]

...Is there a downside apart from the installation cost?

Yes. I might come and live in your spare bedroom.

Try to find someone from the electricity company who is working around your area and explain your situation. They will know the correct terminology to use with the people to whom the money must be paid or the quote requested. It is just like with BT. The local engineer has local knowledge.

I don’t understand why I have 3 x 100amp fuses then.

The fuses look like a relatively recent install, to replace some ancient thing that was there. The electricity board will replace like with like. They are hugely unlikely to put three fuses there if the incoming cable only had one phase and neutral.

The big cost of three phase is the cable coming from the ground. The photo you have posted suggests your one is OK and as said above, you just need a new meter and two more brown tails from the top of the unused fuses.

A cheap way to find out might be to put a contactless voltage detector at the bottom of each fuse and see if it lights up.

 

[scottmk1]

My standing charge for 3 phase is the same as single phase in a domestic property. It cost nothing to get the meter, although I did have to pay to bring 3 phase in from the street.

 

[Munkul]

Even at £1500 its worth it all day long. 3 phase is the boy. I'd be stuck without it.

If you want to run welders over 250 amps then you have very few decent single phase options, and it's a hard load on a single phase supply. Plus all the market for 3 phase machine tools. Everything runs better on higher volts, and everything runs better on more phases. One single digital meter across phases. Unbalanced loads cost electric companies money, it's in their interest to have 3 phase loads if possible.

Way back when, in the late 70s I believe, my Granddad told the national grid we wanted 3 phase on the farm for running farm machinery - putting in a tower silo with automated feeding, a grain crusher, a hay drier shed, etc, all very power hungry. They quoted £8k to bring the 11kV lines to us with a step-down transformer, but he told them if they did it for free, we would install much more equipment and buy correspondingly more power units.

They did it for free. Best deal ever.

 

[grim_d]

I don’t understand why I have 3x 100amp fuses then.

Any number of possibilities, I have two meter heads (fuses) on mine as next door used to share the supply...until I told em to naff orf.

 

[DennisCA]

Remember, you’ll pay standing charges on all 3 meters.

I got three phase and I only got the one meter.

 

[Barking Mat]

Me too. 3ph 1 meter.

 

[Barking Mat]

Random thought.

Can't really tell from the photo, is it possible you've 3 ph coming in, and only 1ph used?

From the photo it's impossible to tell underneath the 3 fuse box.

Get a voltmeter, on ac, and see what voltage is between the fuses.

You could have 3 ph possibly.

Is the cable going out the house buried, where does it to go if it's aerial?

 

[Barking Mat]

Beat me to it @Agroshield ..

 

[scottmk1]

Me too. 3ph 1 meter.

Me 3 it's the same as @Spark plug

 

[Mikes]

I don’t understand why I have 3x 100amp fuses then.

The important thing to determine is if the two other fuses are connected to incoming lives in the supply cable. Could just be a three phase Henley block used on a single phase cable. You don't say what your property is. Is it just a residential house or was there a commercial premise attached? For a long while, the power companies did not want to give 3 phase supplies to purely residential places.

 

[Hopefuldave]

The important thing to determine is if the two other fuses are connected to incoming lives in the supply cable. Could just be a three phase Henley block used on a single phase cable. You don't say what your property is. Is it just a residential house or was there a commercial premise attached? For a long while, the power companies did not want to give 3 phase supplies to purely residential places.

Near me where a few people I know live is a late 40's - early 50's council / ex-council estate, built when Britain's Atomic Powerhouses were going to produce electricity "too cheap to meter" (hah!), all had electrical storage or blown-air heating when built and 3-phase because of the power requirements being more than single-phase could handle - I'm jealous of Eric's 3 x 100A supply, almost as jealous as I am of his workshop...

IF I'm ever rich, I'll get somewhere with 3-phase and retire the rotary converter.

Dave H. (the other one)

 

[sparkysy]

I would imagine that they would be connected to the cut out with no fuses in the carriers, should be a simple case of checking that they are energised, if they are new tails new meter and fuseboard if it's only single phase at the moment and away you go! Standing charges should be similar to single phase. 1500 sounds a lot for a new meter and a couple of meters of tails, I would get them to re-quote, have they been and had a look or seen a photo that may cheapen the deal!
As an aside a lot of estates will have maybe 1 or 2 houses with 3phase where the original site cabins and mortar mixing station were placed while construction of the houses was being done, once finished the kit is taken away and the last house built ending up with a 3ph supply, but only 1ph connected!
Sy

 

[MCKDAVID]

frankly even at 1500, it's cheap. The main advantage is the price / quality of Kit, I've always found 3ph usually cheaper, and better industrial quality (although usually far bigger / heavier), with single phase material at a premium. If you compare the cost of getting three phase in to the additional cost you pay for machines etc, and then the associated VFD, rotary inverters etc... it will soon recoup that investment. worth having no doubt for me...

 

[jimbo84]

Looking at that cut out you've got the potential for 2 phases of free electric

 

[Barking Mat]

Is that those little anti fiddle lead things on the fuses.

How do you know if there are fuses in there?

I reckon they wouldn't bother putting the lead anti fiddle things on if they weren't live.

 

[jimbo84]

Is that those little anti fiddle lead things on the fuses.

How do you know if there are fuses in there?

I reckon they wouldn't bother putting the lead anti fiddle things on if they weren't live.

Yeah it's got the seals on all the fuses. Someone mentioned above they wouldn't put a 3 phase cut out in if it wasn't 3 phase incoming cable and I'd agree.

 

[500e]

This is MY home 3phase feeding house & remote workshop/office, Had it installed in when we built the house

 

[Hopefuldave]

Is that those little anti fiddle lead things on the fuses.

How do you know if there are fuses in there?

I reckon they wouldn't bother putting the lead anti fiddle things on if they weren't live.

Evilbay item 132332764240 - just sayin'

Dave H. (the other one)

 

[Barking Mat]

Yeah, but you'd need the electricity boards special pliers with a stamp on them no?

Or has that all changed?

 

[eLuSiVeMiTe]

If the supply is already there, you should only need a new meter and costs should be no ware near £1500.

Post a pic of what you have, I suspect you have been quoted to have a new supply installed not just replace the meter, if that’s all that’s required.

Same boat here 3p in to the meter for an old heater setup but only one tail to the DB.
Often debated getting a 3p DB installed but happy with my Vfds