AC tripping fuse

The switches might be only switching the live so you will have to disconnect the wiring from each unit , but220 volt can kill
 
The switches might be only switching the live so you will have to disconnect the wiring from each unit , but220 volt can kill

Agreed - disconnect all the A/C systems.
You have to get to a stage where you can switch on the A/C without anything tripping.
It seems that this could be a long job - maybe start by completely disconnecting the raw water pump (all wires).
 
Have you tried running from the generator with shore power disconnected....as in lead unplugged completely from the boat?
 
How far apart are the shore connection points ?

I wonder if you are tapping in to two different phases, the resultant current surge when these connect would instantly knock the breakers out.

If you put a multimeter between the two lives the voltage should be 0. If you are on two different phases it will be 380 - 400 volts. In this case immediately disconnect one supply and speak to the Marina staff about the power distribution layout to the pontoons.
 
How far apart are the shore connection points ?

I wonder if you are tapping in to two different phases, the resultant current surge when these connect would instantly knock the breakers out.

If you put a multimeter between the two lives the voltage should be 0. If you are on two different phases it will be 380 - 400 volts. In this case immediately disconnect one supply and speak to the Marina staff about the power distribution layout to the pontoons.

They only have one point, my shore power lead splits it into 2 at the boat end.
 
How far apart are the shore connection points ?

I wonder if you are tapping in to two different phases, the resultant current surge when these connect would instantly knock the breakers out.

If you put a multimeter between the two lives the voltage should be 0. If you are on two different phases it will be 380 - 400 volts. In this case immediately disconnect one supply and speak to the Marina staff about the power distribution layout to the pontoons.

I wouldn't worry about being connected to two phases.
Yes, it is a risk but if the boat was designed by a reputable boat builder, the two phases will be completely separate on the boat.

For example, I know that ours is plugged into two different phases - it has been ever since we have been in Sant Carles - 12 years now.
And when on a visiting berth, sometimes we can only connect to a three phase shore supply - in this case, I have a 3 phase (red) plug with two separate (blue plug) single phases wires coming out.

In theory, you are absolutely correct but in practise, it is quite safe to connect two separate phases.
 
We have not been told what size shore power or geny .

So thus far I understand the Aircon breaker on the the shore or AC panel trips when attempts to turn the Aircon on with either shore power or geny ( independent of shore lead ) .

So the fault lies with the Aircon equipment not the respective power supplies .

A Current surge is tripping .
From the Aircon unit comp motors or the water pump .

Could it be assuming both trip switches are ok as it’s a huge coincidence if both have failed simultaneously .- that a capacitor, or the thing that ramps up the starting spike to one or more of the Aircon unit compressor motors has failed ?

So if the shore is 32 A and geny [ insert KvA ] because of the failed “ current start surge device “
( sorry I don’t know correct terminology is it capacitor ? ) as soon as the Aircon is switched on it trips out due the load demand of the now naked piece(s) of equipment.

Your control panels of the units just do that control .
The breakers power them up , get power to the motors and one or more is tripping out .

It could be a comp motor is stuck twixt commutator position aided by age / wear and dirt so it’s needs a helluva current to initially turn hence the overload .In which case a rubber mallet tap may free it up as someone switches the breaker on .

So as said one by one disconnect the power to each unit at the unit end and test .
Obviously pull the shore power lead each time and turn the geny off to prevent electrocution .

Edit do the same with the water pump first ...... as it may be stuck .....can you turn it incase it’s a twixt dirty commutator ?They usually have an end wherby you can get a spanner on to turn them .
It may be jammed some debris in its impeller so its motor hums can’t turn overloads and trips .
You should be able to manually turn it or dismantle the pump part to free it up .
 
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You need to eliminate water ingress to the water pump motor and the 4 units .
When was the last time you clean the drip trays and checked there drains are clear ?
 
He is tripping the rcd which is showing an earth fault, he has to disconnect one unit at a time , if he is not confident to do that he needs some one who is
 
Agreed +1000

Working my way, just doing a visual check, I am stupid enough to have a go and disconnect them, but there's a big sticker that says caution...you are at risk of death, and I think my dog would miss me.....so sticking to a visual check only. First one I checked was in master cabin..under the bed, the earth wire was loose, the screw it was connected to, was just barely hand tight...thought I might have fixed it..but it didn't. Visual check will continue :)
 
Working my way, just doing a visual check, I am stupid enough to have a go and disconnect them, but there's a big sticker that says caution...you are at risk of death, and I think my dog would miss me.....so sticking to a visual check only. First one I checked was in master cabin..under the bed, the earth wire was loose, the screw it was connected to, was just barely hand tight...thought I might have fixed it..but it didn't. Visual check will continue :)

If you are worried about safety, just unplug your shore supply - completely.
I suggest that you then go to your A/C raw water pump.
Disconnect the electrical wires from it and insulate them.
Then power up and see if it still trips.
I suggest that the raw water pump is more likely to be the fault than the actual A/C units.
If it still trips, I would leave the pump disconnected and then start with the A/C inits.
And I don't mean the evaporator (inside) units - I think you said that your system was a split system with separate indoor and outdoor units.
If it is going to be a problem with the A/C units themselves, it is more likely to be the compressor units.
Where are they located?
 
That looks like the control box for the raw water pump.
If any A/C unit "calls for" heating/cooling, this controller runs the pump.
I can't see anything wrong with it - can you?

Nothing visual, I thought it was the terminals for all of my units, plus the pump..I have 6 individual units and some are a mare to get too..I thought I might be able to disconnect from this junction, but nothings ever that easy lol
 

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