Shore power

[BobFord]

I would appreciate advice on shore power. My down lead has a 240VAC heavy cable with a 3 phase 32 amp plug. The plug is wired to only take normal single phase supply. ( not sure if this is the correct term , should I say two phase wiring ? ) Anyhow . the idea is to have better than 10 amp supply. How many amps would be available to me if the shore power is rated 32 amp ?

[PaulinOz]

"should I say two phase wiring" not unless you have two phases wired then you will have 415 volts AC between each phase and 240 volts AC from each phase to neutral. Not likely unless your "240VAC heavy cable" is 4 or 5 wire.

I suspect you have one phase, neutral and earth. "The plug is wired to only take normal single phase supply."

A 32 amp plug can safely deliver 32 amps per phase.

A 32 amp 3 phase shore power socket, can supply 32 amps per phase.

What is the current ratting on you "240VAC heavy cable" that may well be the deciding factor. Heavy cable can refer to the amount of physical protection as well as to a higher current capability.

[BobFord]

Thank you for the info. PaulinOz. I don't know the down-lead rating, just that it is very heavy compared to a regular 10 amp of the same length.( So technical, I hear you say !! ) My issue is with the quality of the single phase. The Power Box poles on the dock ,were recently renewed and ever since, I have to be very careful not to trip , even with , to my mind ,normal domestic loads.Microwave , coffee maker etc. Doing the sums , can't ever approach 32 amp.Closer to 12 amp , at absolute peak, in my opinion.Appliances are 240VAC.

[PaulinOz]

Bob are you tripping a 32 amp circuit breaker or a RCD (residual Current device, safety switch).

[BobFord]

The 'tripping' is occuring at the marina's shore pillar. All that's vis. is a typical switch that feels like it ' sets' when reloaded. There is a choice of 32amp sockets , all seem to have the same value.

[Captsteve53]

Even if recently replaced have seen plenty of mal-functioning circuit breakers out of the box, could also just need the wires tightening up (bad installation) but would be the Marina's concern and liability to check/repair,(needs a registered sparky)

You are correct in saying single phase - 3 wire (Phase/ Neutral /Ground).

When calculating your amperage dont for get that the start up load can exceed the running load by upwards of 3 times (for a micro second or so).

If your power lead is too small in cross section wire diameter it can/will cause heat and possible over loading of breakers, but put my money on a dodgy CB.

Cheers Steve

[smac999]

You need more info. I have never seen A 240v 32a breaker.

North America is 240v but runs 50a breakers. Giving you 50a on each split phase leg. So 100a of 120v is using all wires. And 50a if only using one leg.

If you have a 32a breaker you are probably on 230v euro power. In which case there is only one leg. And no way to use less wires. You will get 32a

[Captsteve53]

Just for info: Both Australia and New Zealand has 240v 50 Hz as a standard power supply where 15/20/25/32 amp breakers are the norm, using a three wire system (Phase/Neutral.Ground).

[Zven]

It would help if the OP explains where in the world he is...?
32 amp seems a common rating for cables and breakers at marinas in Europe and SE Asia.

[BobFord]

Hey Sven !, check my location , it hasn't changed in the last 2 years. And thanks people for the very useful input, Cheers, Bob