New Three Phase Connection

[Woodcraft]

Hi All,

I'm currently trying to get a quote for a new three phase connection, but I'm a little out of my depth

I have been asked for various information on the tools and equipment that we will be using on three phase, but this is quite hard as we don't have any... everything we have is single phase and will be run from our existing supply
So I suppose I'm going to have to guess our requirements?

We have a mixture of things going on here but the main use of three phase will be for workshop equipment, Welder, Plasma Cutter, Band Saws etc

Just wondering if any one can help with a predicted kVA? and what size transformers do you have on your farms?

Thanks

 

[Bob c]

https://thefarmingforum.co.uk/index.php?threads/3-phase-connection-cost.12212/

 

[upnortheast]

Chat to a sparky with experience of big kit, not the guy who makes his money putting downlights in for yummy mummys.

We put 3 phase in 2 years ago. We added up the load which came to about 45kw. So went for 90.to allow for future growth.

Northern Powergrid charged £27000 then the sparkys bill was about £6000. Was`nt very complicated but 100 metres cable from meter to our distribution point was £1000. 160 amp 3ph switches, fuses etc seem to be about 4 times the price of 100 amp single ph kit

 

[Woodcraft]

The transformer and connection is all at the pole, we aren't planning on running the cable to the yard or fully connecting up right away.
UK Power are putting an overhead cable that crosses our yard underground, they've said they would really like us to put three phase on at the same time, as the cable they are re routing is high voltage and supplies power to half of the next town/village, so they want to minimise the amount of times this is turned off.. which is fair enough

So really, seeing as there already bringing the cables down the pole to ground level any way.. splicing a couple of other cables in shouldn't be toooooo expensive (in definitely will be though, i'm sure)

 

[Greenbeast]

We had ours installed this April, £4300 for a 45kVA supply. We then spent about £3-4k running it underground across the farm. (180m of 35mm2 5 core swa, all the bits both ends and the sparky's time to terminate)
Connection would have been considerably cheaper had the poles been on our side of the road. The ground works were about £3k

 

[Woodcraft]

so what are you running on a 45kVa supply then?

 

[Greenbeast]

nothing yet, same as you, and we're a free range pig farm, so i doubt the 'farm' will ever be a major draw, but i have plans to re-establish my 'smithing workshop...

bear in mind it's 100A PER PHASE, so effectively a 300A supply if you run a lot of single phase gear (and split between the phases)

 

[cat]

we had it put in 8 years ago and went with a 100 kva tranny. if i remember up to and including 100 was a set price, anything above started getting expensive, 100 runs a large workshop, a dryer and the feed-mill. Ours cost £38k + £12k for a sparky

 

[Pheasant Surprise]

we had it put in 8 years ago and went with a 100 kva tranny. if i remember up to and including 100 was a set price, anything above started getting expensive, 100 runs a large workshop, a dryer and the feed-mill. Ours cost £38k + £12k for a sparky

Correct, up to and including 100A per phase is quite straightforward. It will easily handle what the OP wants.

Beyond 100A per phase and you're really into the big stuff and big money. Not only do transformers get really expensive but so do the day to day things like metering.

Edit: 100A per phase supply is a 72 kVA connection. More than enough for what you need.

Personally I wouldn't bother with a 60A per phase connection (43kVA), as you may find it unnecessarily limits you, so make sure your kit adds up to more than that! @Woodcraft

Another 100A three phase thread:
https://thefarmingforum.co.uk/index.php?threads/3-phase-100amp.12557/

 

[Pheasant Surprise]

The transformer and connection is all at the pole, we aren't planning on running the cable to the yard or fully connecting up right away.
UK Power are putting an overhead cable that crosses our yard underground, they've said they would really like us to put three phase on at the same time, as the cable they are re routing is high voltage and supplies power to half of the next town/village, so they want to minimise the amount of times this is turned off.. which is fair enough

So really, seeing as there already bringing the cables down the pole to ground level any way.. splicing a couple of other cables in shouldn't be toooooo expensive (in definitely will be though, i'm sure)

They don't like routinely switching off the > 11kV as it requires notice etc and they need to get their "hot crew" out to do it.

 

[Woodcraft]

Thanks for the replies, very helpful!

I'll see what they say

 

[Steevo]

I got a quick quote from them recently for a 3ph upgrade. 75kva was £50k and 150kva was the same money!

 

[Newburn Power]

It would certainly be cheaper and easier to Buy a 3 phase New Generator, if you are just running work shop equipment.

 

[Badshot]

The rules are changing, speak to your supplier about monthly charges, capacity charges and environmental charges.
Up to 100kva used to be ok, above meant half hourly metering and loads of standing charges. The limits have been dropped a lot and most people will be on half hourly metering in the near future.

 

[upnortheast]

Heard an ad on the radio the other day offering free leccy at certain times of the day if you have a "smart meter" - half hourly metering.

Looks like that is the way the market is going

 

[Courier]

We were constantly overloading our 11kVa single phase connection when we were milking and pasteurising and bottling with all the refrigeration and processing equipment. We were using electic heating on both the bottle washer and the pasteuriser as well as a 5hp motor (480 volt split-phase) on each the vacuum pump, the separator and the homogenizer.. We also had an on floor 15hp (480 volt grain drying fan which took about 70 seconds to build up speed on a manual capacitor start ( That used to dim the lights somewhat) . They approached us and told us that they would upgrade the supply to 3 phase FOC.

2 years later we packed up with the cows and now the only three phase motor we regularly now use is a roller shutter door opener

However the upgraded supply gave us the opportunity to get a 200 kWh wind turbine which is producing more kWh than we had milk quota and at around 25p per unit all in.

 

[TripleSix]

Heard an ad on the radio the other day offering free leccy at certain times of the day if you have a "smart meter" - half hourly metering.

Looks like that is the way the market is going

That's a British Gas promotion for their duel fuel customers only....

 

[bigw]

We have just put an additional supply in here and was the same as you @Woodcraft with not knowing what size of supply to put in. SSE phoned me up about the application and were really good and just priced the biggest possible supply I could get without changing transformers etc.

I ended up with 19kva which cost about £600. The cable run was very short and the whole thing was done live as they just spliced into an underground cable using a clamp type fitting.