Shore power splitter

[cmedsailor]

My new boat has two shore power sockets. One for the aircondition and for general shore power connection. I also have two separate shore power cables. The usual 3-pin 16A male plug on one side (shore) and the female side for the boat. Could anybody recommend me a good quality shore power splitter (one 3 pin male - two 3 pin female)?
Thanks

 

[VicS]

Is this what you want

If so look at caravanning supplies websites eg https://www.towsure.com/3-way-caravan-camping-site-mains-connector

Dont overload the pontoon outlet by trying to take more than 16 amps.
2 way splitters are also available.

 

[Alex_Blackwood]

My new boat has two shore power sockets. One for the aircondition and for general shore power connection. I also have two separate shore power cables. The usual 3-pin 16A male plug on one side (shore) and the female side for the boat. Could anybody recommend me a good quality shore power splitter (one 3 pin male - two 3 pin female)?
Thanks

Not a good idea. Suspect that your a/c will take most load. Combine the two and you will be constantly tripping the shore breaker. May also cause excessive heat in the single socket. Don't do it!

 

[RichardS]

Not a good idea. Suspect that your a/c will take most load. Combine the two and you will be constantly tripping the shore breaker. May also cause excessive heat in the single socket. Don't do it!

The problem then is that you are taking up two 16A outlets and these are often in short supply in busy marinas so someone is, not unreasonably, going to unplug one of your lines whilst you are not onboard. I've seen/done this several times so I wonder whether people with two lines should indicate with a label which one has the lowest priority. :encouragement:

The ideal solution would be a 32A male to 2 x 16A female as 32A outlets often seem to be available.

Richard

 

[Alex_Blackwood]

The problem then is that you are taking up two 16A outlets and these are often in short supply in busy marinas so someone is, not unreasonably, going to unplug one of your lines whilst you are not onboard. I've seen/done this several times so I wonder whether people with two lines should indicate with a label which one has the lowest priority. :encouragement:

The ideal solution would be a 32A male to 2 x 16A female as 32A outlets often seem to be available.

Richard

Fair comment about taking up two supply outlets. However it does not solve the problem of electrical loading. It is possible for a MCB to take around 110% overload for a prolonged period, this applies irrespective of whether you have one or two plugs in. However it is more likely with two. If you take two 16 amps from a 32 amp socket you can end up pulling 32 amp+ through a 16 amp socket! A complete No-No! My professional opinion and advice is don't do it.
As a matter of interest we have had socket burn out at my club because of the use of a splitter.

 

[prv]

If you take two 16 amps from a 32 amp socket you can end up pulling 32 amp+ through a 16 amp socket!

How does this work, unless the boat is already wired wrong? Surely any system that ends with a 16 amp plug is going to be designed not to draw more than 16 amps - in the case of a boat by having a 16 amp breaker on the incoming supply?

Agree that if the boat has been designed with two 16 amp inlets because it needs more than 16 amps to run all the toys, then trying to run it all off one is going to cause problems. Shouldn't be dangerous problems if everything works as it should, just inconvenient problems of constantly tripping breakers. Richard's suggestion of a 32A plug is a good one if the sockets are available where you sail (I'm not sure how common they are around here, though they do exist).

Pete

 

[RupertW]

I’d echo the point about taking up 2 outlets leaving others with none. My usual rule if somebody has taken two is to wait until the air conditioner goes off (assuming they have the normal noisy splash into the water near my open hatches) and pull out the plug to put mine in. Better if they are awake or around so I can ask but some people are very aggressive about keeping 2 and denying others one.

 

[Graham376]

Fair comment about taking up two supply outlets. However it does not solve the problem of electrical loading. It is possible for a MCB to take around 110% overload for a prolonged period, this applies irrespective of whether you have one or two plugs in. However it is more likely with two. If you take two 16 amps from a 32 amp socket you can end up pulling 32 amp+ through a 16 amp socket! A complete No-No! My professional opinion and advice is don't do it.
As a matter of interest we have had socket burn out at my club because of the use of a splitter.

I don't understand your reasoning. He's talking about 1 x 32amp plug which splits into 2 x 16amp sockets, one for each of his onboard separate systems. How can he pull 32+ amps through one 16amp socket?

 

[VicS]

I don't understand your reasoning. He's talking about 1 x 32amp plug which splits into 2 x 16amp sockets, one for each of his onboard separate systems. How can he pull 32+ amps through one 16amp socket?

The objection surely is that he would have 2 x leads, boat connectors and some internal wiring all rated at 16 amps but "protected" by the 32 amp circuit breaker in the pontoon power pedestal. They should be protected by 16 amp breakers or fuses at source.

 

[PCUK]

Slight thread drift but in the event of no spare sockets I have a splitter and after unplugging the one in use, plug my splitter in and reconnect them both. No problems so far

 

[Graham376]

The objection surely is that he would have 2 x leads, boat connectors and some internal wiring all rated at 16 amps but "protected" by the 32 amp circuit breaker in the pontoon power pedestal. They should be protected by 16 amp breakers or fuses at source.

Understand your reasoning but presumably, each of his boat's supplies will be protected by its own rcd and breaker to cater for faults and overload and, the shore rcd will trip if problem with shore leads, regardless of current draw. Whist it's technically maybe incorrect, I would be quite happy in practice.

 

[johnalison]

Slight thread drift but in the event of no spare sockets I have a splitter and after unplugging the one in use, plug my splitter in and reconnect them both. No problems so far

Don't do what I did in deepest Holland and find that you have shared a metered socket and not paid for it. The owner was very good about it and it only cost me a beer.

I made up my own splitter with the usual terminals and some cable. I have never had any difficulty in tripping shore facilities when overloading, but would be alarmed if I thought the sockets were not protected.

 

[VicS]

Understand your reasoning but presumably, each of his boat's supplies will be protected by its own rcd and breaker to cater for faults and overload and, the shore rcd will trip if problem with shore leads, regardless of current draw. Whist it's technically maybe incorrect, I would be quite happy in practice.

There will , hopefully , be an RCD in the pontoon pedestal which should trip (faster than the circuit breaker), in the event of a line to earth fault but not in the event of a line to neutral fault or an ovecurrent situation. You rely on the circuit breaker to trip in these cases.

It is a bad idea to rely on an RCD anyway because they are electronic devices which can fail and they do not fail safe. They fail to trip! The circuit breaker should have two tripping mechanisms, a magnetic one which should trip quickly in the event of a large over-current, and a thermal one which will trip more slowly in the event of a continuing smaller over-current.

The boat's internal circuits will be protected by the RCD and circuit breakers in the consumer unit. Possibly also by an circuit breaker between the inlet connector and the consumer unit.

Perhaps you should not be so happy

For anyone wanting to know more about the operation of RCDs and circuit breakers I recommend John Ward's videos.