PierreR
Guru
- Joined
- Oct 7, 2022
- Messages
- 564
- Vessel Name
- Mar Azul
- Vessel Make
- 1977 Hatteras 42 LRC
I gained a lot of information from this thread. Enough to maybe talk some sense.
https://www.trawlerforum.com/forums/s4/isolation-transformer-neutral-ground-connections-70843.html
I bought my boat 15 months ago in Madisonville LA and needed to get the boat back to Sandusky Ohio. This boat had no inverter and I was faced with running the generator the whole time I was enroute or installing an invertor. The generator at the time was new and was not wired in. Original internal electric controls for the generator did not exist. I had to figure that out.
I wired in the invertor (Victron MultiPlus 2KVA 120V) as per instructions. The invertor switches fine from shore power to invertor but not the other way around. With everything off that draws power, I can switch on shore power. When I do, I get a temp overload that switches to charger mode in a minute or so and then I can turn things back on. If I have much of anything drawing power I need to turn everything off and reset the invertor.
Should be easy enough to fix except that I have zero wiring diagrams for this boat. No circuits what so ever.
there are at least two isolation transformers and I suspect there is a third hidden out of sight that controls two of the three air conditioning units.
The boat owners manual said the boat came with two 30amp shore power circuits two two transformers. One hidden out of sight and one the lazarette. Current shore power is one 50amp 240v to a 15KVA 120/240 transformer and one 30 amp 120 v. to a 5KVA 120/240v transformer. I suspect the third is 5KVA 120/240 as well. There is a switch with 120V-off-240V and a manual Generator transfer switch.
When on 50amp shore power and the switch in 240 volts, I can measure 240 volts between the two halves of the AC panel and I have all AC units operable. When I am on 30 amp 120v with the switch in 120v I measure 120 volts between the two halves. Everything will work but I only have 30 amps to work with. I also have a 50 amp 120v cord that gives me 50 amps everywhere when switch is in 120v. I determined the original generator was hooked up 120v so I did the same with the new generator. I have nothing on the boat that uses 240 volts
I have every reason to believe the AC shore power system was hooked up by a professional as neither of the two previous owners were electrical savvy. After reading the referenced thread above the problem might be as simple as me not understanding these transformer grounds can be wired two ways and I picked the wrong one in hooking up the invertor.
I will be going to the boat tomorrow and attempting to figure out how things are wired from shore power and make a diagram so we can talk some sense. When I say attempting that does not me I question my capability of understanding. It means my body may not cooperate in the spaces allowed. 15 weeks out of rotator cuff surgery. There are places in this boat that I have not actually seen yet. I had a 19 year old on board for the trip that could get into those spaces and describe for me what was there.
Time for some detective work. Could I hire this work to be done? Yes but there is still no wiring diagram and I would still not understand what I have. Time to get one of those meters that is wireless for continuity.
https://www.trawlerforum.com/forums/s4/isolation-transformer-neutral-ground-connections-70843.html
I bought my boat 15 months ago in Madisonville LA and needed to get the boat back to Sandusky Ohio. This boat had no inverter and I was faced with running the generator the whole time I was enroute or installing an invertor. The generator at the time was new and was not wired in. Original internal electric controls for the generator did not exist. I had to figure that out.
I wired in the invertor (Victron MultiPlus 2KVA 120V) as per instructions. The invertor switches fine from shore power to invertor but not the other way around. With everything off that draws power, I can switch on shore power. When I do, I get a temp overload that switches to charger mode in a minute or so and then I can turn things back on. If I have much of anything drawing power I need to turn everything off and reset the invertor.
Should be easy enough to fix except that I have zero wiring diagrams for this boat. No circuits what so ever.
there are at least two isolation transformers and I suspect there is a third hidden out of sight that controls two of the three air conditioning units.
The boat owners manual said the boat came with two 30amp shore power circuits two two transformers. One hidden out of sight and one the lazarette. Current shore power is one 50amp 240v to a 15KVA 120/240 transformer and one 30 amp 120 v. to a 5KVA 120/240v transformer. I suspect the third is 5KVA 120/240 as well. There is a switch with 120V-off-240V and a manual Generator transfer switch.
When on 50amp shore power and the switch in 240 volts, I can measure 240 volts between the two halves of the AC panel and I have all AC units operable. When I am on 30 amp 120v with the switch in 120v I measure 120 volts between the two halves. Everything will work but I only have 30 amps to work with. I also have a 50 amp 120v cord that gives me 50 amps everywhere when switch is in 120v. I determined the original generator was hooked up 120v so I did the same with the new generator. I have nothing on the boat that uses 240 volts
I have every reason to believe the AC shore power system was hooked up by a professional as neither of the two previous owners were electrical savvy. After reading the referenced thread above the problem might be as simple as me not understanding these transformer grounds can be wired two ways and I picked the wrong one in hooking up the invertor.
I will be going to the boat tomorrow and attempting to figure out how things are wired from shore power and make a diagram so we can talk some sense. When I say attempting that does not me I question my capability of understanding. It means my body may not cooperate in the spaces allowed. 15 weeks out of rotator cuff surgery. There are places in this boat that I have not actually seen yet. I had a 19 year old on board for the trip that could get into those spaces and describe for me what was there.
Time for some detective work. Could I hire this work to be done? Yes but there is still no wiring diagram and I would still not understand what I have. Time to get one of those meters that is wireless for continuity.