16 or 32 amp...which can I use?

SeaAndSea

SeaAndSea

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How do I know whether I can plug into 16 or 32amp shore power?

When plugged into 16amp I can hardly use anything on the boat without trying the RCD on the pontoon tower.

PO had left cables and adaptors for many different connections including 32amp.

I don't want to cause any problems, or a fire.

Colin
Trader47
Essex Marina
 
You can use either it makes no odds ---- other than the 32 amp one will supply more power.

If you are going to use more than 16 amps ( which on a boat is pretty simple to do ...) then do make sure your shore cable is rated accordingly. If not it will get warm/ hot etc.

You boat probably has a breaker on the shore supply that will trip at a nominal 16/ 32 amps depending on what it was designed for
 
jrudge said:
You boat probably has a breaker on the shore supply that will trip at a nominal 16/ 32 amps depending on what it was designed for
Click to expand...
Agreed, but it's worth mentioning that, even with breakers at both ends (downstream the onboard socket and upstream the dockside), it is still possible to fry a cable.
I mean, if the sockets are 32A, more than likely also the breakers are, so neither of them would trip before overheating/cooking a 16A cable.
 
You can’t underestimate the significance of correct cable size to pull what ever it’s asked to pull .
Ours is a 32 A boat but has a massive and awkwardly heavy cable .
We had it in ( via adaptor) in a red 64 A ..no issues .
Also I think folks should occasionally open up the socket / plug at each end and “ service “
Check for frying evidence , redo corroded contacts and such like .
They are susceptible to water ingress or inadvertent tug and corrosion etc etc ...even with the best set ups there’s an inevitability here so if you haven’t “ serviced “ them put it on your list of to do jobs .
 
The size of the socket on the boat should make it fairly clear what it is expecting - unless some cowboy has swapped an original 32 amp socket for a 16 amp socket. If it was built as a 16 amp system, there is no particular risk associated with connecting it to a 32 amp socket on the pontoon - the circuit breaker in the boat should limit the drain to the 16 amps that the connector can carry. The other way round should also be safe provided the circuit breakers on the pontoon side are working - plugging a boat wired for 32 amps up to a 16 amp pontoon outlet could certainly overload the pontoon installation with a risk of wiring and connectors overheating, but the breaker should trip long before that becomes a problem.
 
maby said:
The size of the socket on the boat should make it fairly clear what it is expecting - unless some cowboy has swapped an original 32 amp socket for a 16 amp socket. If it was built as a 16 amp system, there is no particular risk associated with connecting it to a 32 amp socket on the pontoon - the circuit breaker in the boat should limit the drain to the 16 amps that the connector can carry. The other way round should also be safe provided the circuit breakers on the pontoon side are working - plugging a boat wired for 32 amps up to a 16 amp pontoon outlet could certainly overload the pontoon installation with a risk of wiring and connectors overheating, but the breaker should trip long before that becomes a problem.
Click to expand...

May be you should not comment on electric when not correct.
 
seastoke said:
May be you should not comment on electric when not correct.
Click to expand...

What did I say that is incorrect? There is certainly no risk from plugging a 16A wired boat to a 32A socket - the circuit breakers on the boat are the first line of defence against problems. I agree that plugging a 32A wired boat up to a 16A pontoon socket is wrong, but the pontoon circuit breakers will protect against overloads provided they are in working order.
 
32A to 16A is not wrong - it will just pop the breaker if the current demand on the boat is not managed.

Sometimes 16a is all there is. In my experience I can tease about 20amps ( as indicted on my panel) before it trips.
 
Big_Col said:
How do I know whether I can plug into 16 or 32amp shore power?

When plugged into 16amp I can hardly use anything on the boat without trying the RCD on the pontoon tower.

PO had left cables and adaptors for many different connections including 32amp.

I don't want to cause any problems, or a fire.

Colin
Trader47
Essex Marina
Click to expand...
Nuisance breaker tripping is often due to the Curve rating of the MCB devices on the pontoon tower. If you are running anything with AC motors such as washing machines or tumble driers, even though their base-load will likely be less than 13a, the motor start current trips the breaker, certainly if they are B rated and sometimes even with C rated, but few marina supplies use D rated MCBs.

AC Compressors will easily trip a 16a C rated MCB, especially if cycling on a decent load.

It is simple to ascertain what breakers are provided - the code will be visible on the breaker (sometimes combined with the RCD device) e.g. C16 for a C rated 16a, or B32 for a B rated 32a.
 
maby said:
What did I say that is incorrect? There is certainly no risk from plugging a 16A wired boat to a 32A socket - the circuit breakers on the boat are the first line of defence against problems. I agree that plugging a 32A wired boat up to a 16A pontoon socket is wrong, but the pontoon circuit breakers will protect against overloads provided they are in working order.
Click to expand...

well take my boat it has 4 times 16amp breaker and 1 ,6 amp breaker , if I am in a 16 amp on the pontoon the pontoon breaker limits me to 16amp safe . Now if I change the plug to 32amp and plug in then the immersion is on electric heater say kettle battery charger which could spread the load towards say 20amps what is protecting the mains lead rated at 16 amp and the 16 amp fixed socket and the 16amp trailing socket ,that melts and sets the boat on fire . the insurance investigation find this will they pay out I don't think so. not criticizing just trying to help
 
seastoke said:
well take my boat it has 4 times 16amp breaker and 1 ,6 amp breaker , if I am in a 16 amp on the pontoon the pontoon breaker limits me to 16amp safe . Now if I change the plug to 32amp and plug in then the immersion is on electric heater say kettle battery charger which could spread the load towards say 20amps what is protecting the mains lead rated at 16 amp and the 16 amp fixed socket and the 16amp trailing socket ,that melts and sets the boat on fire . the insurance investigation find this will they pay out I don't think so. not criticizing just trying to help
Click to expand...

On my boat, the 16amp breaker next to my shore power socket will trip.
 
seastoke said:
well take my boat it has 4 times 16amp breaker and 1 ,6 amp breaker , if I am in a 16 amp on the pontoon the pontoon breaker limits me to 16amp safe . Now if I change the plug to 32amp and plug in then the immersion is on electric heater say kettle battery charger which could spread the load towards say 20amps what is protecting the mains lead rated at 16 amp and the 16 amp fixed socket and the 16amp trailing socket ,that melts and sets the boat on fire . the insurance investigation find this will they pay out I don't think so. not criticizing just trying to help
Click to expand...
I think the real risk here is relatively low. In practice many distribution boxes are filled with MCBs that added considerably exceed the rating of the supply ampacity, but this misses the point that MCBs are protecting the supply cabling downstream of the MCB, and not what is supplied before. The job of the MCB on the shore supply protects the cable. OK plugging a 16a 1.5mm2 cable into a 32a outlet is possible, but having such a severe draw to cause this to melt let alone catch fire is a bit unrealistic. The 16a rated 1.5mm2 cable will work perfectly safely at 29 amps as a trailed cable in open air, but yes it will get a bit hot (not above safe limits), but it will not catch fire. Indeed the self ignition temperature would likely require at least 50% overload, so way above the 32a rated shore supply breaker.
 
seastoke said:
well take my boat it has 4 times 16amp breaker and 1 ,6 amp breaker , if I am in a 16 amp on the pontoon the pontoon breaker limits me to 16amp safe . Now if I change the plug to 32amp and plug in then the immersion is on electric heater say kettle battery charger which could spread the load towards say 20amps what is protecting the mains lead rated at 16 amp and the 16 amp fixed socket and the 16amp trailing socket ,that melts and sets the boat on fire . the insurance investigation find this will they pay out I don't think so. not criticizing just trying to help
Click to expand...
I'm not sure to get your point.
Regardless of the pontoon socket+breaker capacity, you should have also a main breaker onboard, rated for the total max current that your plug+cable are rated for.
I understand that each specific breaker (for heater, kettle, cooktop, whatever) might not trip, potentially adding up a total current demand well in excess of 16A, but in such case it's that onboard main breaker, upstream of the electric panel, which is supposed to save the day.
If you don't have one, in your boots I'd consider fitting it, as close as possible to the cable connection.
Which as I understand is what petem said that he has on his boat.
 
MapisM said:
I'm not sure to get your point.
Regardless of the pontoon socket+breaker capacity, you should have also a main breaker onboard, rated for the total max current that your plug+cable are rated for.
I understand that each specific breaker (for heater, kettle, cooktop, whatever) might not trip, potentially adding up a total current demand well in excess of 16A, but in such case it's that onboard main breaker, upstream of the electric panel, which is supposed to save the day.
If you don't have one, in your boots I'd consider fitting it, as close as possible to the cable connection.
Which as I understand is what petem said that he has on his boat.
Click to expand...

P, I don't understand his point either. In addition to a 16A breaker adjacent to the shorepower plug, surely Seastoke's boat has a 16A breaker on his 240v consumer board (in additional to the individual 13A breakers for heater, kettle, cooktop, whatever)?
 
I'll happily connect my 70ft boat to a 1 x 16A 230V supply, or aswell to a 3 x 63A 230V supply,
and everything in between,
and the system is made so that there is no inherent risc of fire
 
petem said:
P, I don't understand his point either. In addition to a 16A breaker adjacent to the shorepower plug, surely Seastoke's boat has a 16A breaker on his 240v consumer board (in additional to the individual 13A breakers for heater, kettle, cooktop, whatever)?
Click to expand...

I don't think that the safety regulations which apply to your house extend to boats, so I guess it could be wired up without that overall protector. If the shore power connector on the boat is 32A, then the only way that he could overload the cable would be to use an adaptor at either end of a 16A cable - one inboard to allow him to plug the 16A cable into the onboard socket and another at the pontoon end to plug the 16A cable up to a 32A socket there. This really requires some serious effort at being dangerous!

If the socket on the boat is a 16A type and then feeds multiple 16A breakers, then this is a dangerous installation. I doubt that it would pass the current CE directives and I can't imagine that any serious boat builder has installed anything like this. It is certainly true that the consumer unit may include multiple breakers that add up to more than 16A together, but they are protecting individual circuits - you would still expect to have a single master breaker between the consumer unit and the shorepower socket which is rated at the safe maximum of the shorepower connection.
 
maby said:
I don't think that the safety regulations which apply to your house extend to boats, so I guess it could be wired up without that overall protector. If the shore power connector on the boat is 32A, then the only way that he could overload the cable would be to use an adaptor at either end of a 16A cable - one inboard to allow him to plug the 16A cable into the onboard socket and another at the pontoon end to plug the 16A cable up to a 32A socket there. This really requires some serious effort at being dangerous!
Click to expand...

in any boat installation its save / a obligation to have one main cirquit breaker, in order to cut the shore supply in case of a problem.
this should be rated the size of the supply cable and connectors.

In our boat the two supply sockets and cables are 6mm2 so they can handle 40 amps , so our main breakers are 40 amps.
(unfortunately the sockets are CEE32A, but they can occasionally / intermittantly handle a bit above 32A )

if we connect the boat to 2 x 16A shore supply, the shore supply cirquit breaker will trip if we go above 16A (despite all cabling being rated for 40 amps)
if we connect the boat to 2 x 32A shore supply, we can use maximum 32Amps on each cable.
if we connect the boat to 2 x 63A shore supply, our main cirquit breaker will trip if we go above 40Amps. If there is a short in our 40A cable, in theory this can get fire, but we take that risc, because the chance that this happens is extremely small, and the curent is quickly above 63 amps, so that the 63A shore breaker will trip...

curently the boat is connected to 1 x 90A socket with a splitter to two x CEE32A, 6mm2 cable used for the splitter,
 
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