Wiring isolation transformers

[rourkeh]

I am wondering the proper way to wire the isolation transformer green ground wire on the output side. The instructions have a number of different wiring diagrams. Can you guys let me know what you have done. Cheers.

[SeaEric]

I'm adding isolation transformers this winter as part of a total re-do of the electrical on my 1966 41 TC. My personal participation in the project is mostly limited to scratching the check to the contractor. I do have a pdf diagram that describes the wiring. Its too large to upload here. If you PM your e-mail address I'll send it. It may be of some help to you.

[jim rosenthal]

Were you having an electrolysis problem where you are? That's a big project.

[krush]

Even if yours isn't a charles, this should work: http://www.charlesindustries.com/mar...l/pm3201_1.pdf

A transformer is a transformer. Their diagrams look like they may be from ABYC anyway.

Good article: https://www.deimarine.com/media/wysi...icle_10-20.pdf

[Maurice]

It's my understanding that a Galvanic Isolator prevents electrocution in the event that AC current escapes from the AC wiring on board (i.e. through a short in an AC battery charger), and the AC green ground wire should be bonded to the DC ground on board. It protects the hull, anodes and aluminum parts from galvanic corrosion when plugged into shore power. It is wired into the shore power grounding wire. They are two opposing semiconductor diodes. They prevent low voltage galvanic current leaving or entering the boat but easily allow 110 volts to pass through. Some may offer a monitoring panel -KCB Technologies in Canada ... if not discontinued.
The Isolation Transformer is completely different animal which completely separates the incoming AC power from the DC power on board. The AC power is transmitted electronically through the transformer. It prevents stray galvanic current from the dockside from reaching the boat, and prevents AC power from the dockside from posing a safety hazard for the crew. The AC ground wire is still connected to the DC ground to provide protection against faulty AC circuits on the boat.
By what I read, the galvanic isolator should be on any boat that plugs into shore power. It is lighter and less expensive that the transformer.
The AC and DC electrical systems are to be connected at one common grounding point.
There is a lot of easily understood info on the web about these devices, although I read where there may not be unanimous agreement where the ground wires should go. My opinion, get a qualified expert, and verify the qualifications.

[Passages]

My opinion, get a qualified expert, and verify the qualifications.

Mine too. I had and electrician spend a day on board scratching his head on the best way to tie my iso transformer. He called in HIS expert who still had to make a few phone calls.

They got it done but this is not a DIY project.

I ended up with a ACME 15 KVA iso xformer. Zincs lasting longer and I swear, my metered electric has gone down by a third. As an additional benefit, I don't have to worry about electrocuting my diver with stray current.

[Doug.T]

It's my understanding that a Galvanic Isolator prevents electrocution in the event that AC current escapes from the AC wiring on board (i.e. through a short in an AC battery charger), and the AC green ground wire should be bonded to the DC ground on board. It protects the hull, anodes and aluminum parts from galvanic corrosion when plugged into shore power. It is wired into the shore power grounding wire. They are two opposing semiconductor diodes. They prevent low voltage galvanic current leaving or entering the boat but easily allow 110 volts to pass through. Some may offer a monitoring panel -KCB Technologies in Canada ... if not discontinued.
The Isolation Transformer is completely different animal which completely separates the incoming AC power from the DC power on board. The AC power is transmitted electronically through the transformer. It prevents stray galvanic current from the dockside from reaching the boat, and prevents AC power from the dockside from posing a safety hazard for the crew. The AC ground wire is still connected to the DC ground to provide protection against faulty AC circuits on the boat.
By what I read, the galvanic isolator should be on any boat that plugs into shore power. It is lighter and less expensive that the transformer.
The AC and DC electrical systems are to be connected at one common grounding point.
There is a lot of easily understood info on the web about these devices, although I read where there may not be unanimous agreement where the ground wires should go. My opinion, get a qualified expert, and verify the qualifications.

The problem that I have is that I have two isolation transformers, but then they connect the ground from the shore power to the ground for the boat side, essentially making the isolation transformers useless.

[brettportzer]

I'm adding isolation transformers this winter as part of a total re-do of the electrical on my 1966 41 TC. My personal participation in the project is mostly limited to scratching the check to the contractor. I do have a pdf diagram that describes the wiring. Its too large to upload here. If you PM your e-mail address I'll send it. It may be of some help to you.

Where are they going?

[jim rosenthal]

Who makes isolation transformers, now? I had the impression Charles was out of that market, but perhaps my memory is mistaken.

[Jammin']

Defender still has some Charles units in stock.