Isolation transformer?

[Tananger]

I have just bought a 1999 model Princess 20M .

This yacht does not have an isolation transformer on the shorepower circuit. Is it common practice not to have an isolation transformer?

 

[Alex_Blackwood]

I have just bought a 1999 model Princess 20M .

This yacht does not have an isolation transformer on the shorepower circuit. Is it common practice not to have an isolation transformer?

Most I can say, is. Some do some don't. If the boat is "As fitted" by builder then should be no cause for concern. To go into more detail, on this forum, without seeing the installation is pointless and probably confusing. If you are concerned get a professional on site opinion.

 

[PaulRainbow]

I have just bought a 1999 model Princess 20M .

This yacht does not have an isolation transformer on the shorepower circuit. Is it common practice not to have an isolation transformer?

Isolation transformers are not particularly common, as long as you have a galvanic isolator you'll be fine. If in doubt, get it checked.

 

[Hurricane]

My Princess 67 doesn't have a transformer or a galvanic isolator.
I've never (yet) had any galvanic issues.
She stays connected to the shore power 24/7/365
I bought her from new and I try to keep her well maintained - anodes replaced when needed etc.
No galvanic isolator seems to be the Princess thing.
I know a very knowledgeable friend that bought a new Princess and fitted a galvanic isolator but, in my experience, it isn't necessary.
I have also had friends with transformers fitted to their boats - one such friend had lots of trouble with his transformer.
I would stay clear of transformers.
Your boat is a 1999 model - if she had a galvanic problem, it would have shown by now.
IMO, concentrate on maintaining all the components that Princess fitted - in the case of galvanic protection, check that the shafts etc are well electrically bonded.
BTY - Princess also don't bond their seacocks - there are several schools of thought on that one but, again, I've had no problems - just maintenance when required.
Our boat is nearly 17 years old so younger than yours but still old enough to see any faults.
I hope that helps

 

[PaulRainbow]

My Princess 67 doesn't have a transformer or a galvanic isolator.
I've never (yet) had any galvanic issues.
She stays connected to the shore power 24/7/365
I bought her from new and I try to keep her well maintained - anodes replaced when needed etc.
No galvanic isolator seems to be the Princess thing.
I know a very knowledgeable friend that bought a new Princess and fitted a galvanic isolator but, in my experience, it isn't necessary.
I have also had friends with transformers fitted to their boats - one such friend had lots of trouble with his transformer.
I would stay clear of transformers.
Your boat is a 1999 model - if she had a galvanic problem, it would have shown by now.
IMO, concentrate on maintaining all the components that Princess fitted - in the case of galvanic protection, check that the shafts etc are well electrically bonded.
BTY - Princess also don't bond their seacocks - there are several schools of thought on that one but, again, I've had no problems - just maintenance when required.
Our boat is nearly 17 years old so younger than yours but still old enough to see any faults.
I hope that helps

Galvanic isolators are not there because the boat "has a galvanic problem". They are there because a boat near to you, or the marina has a problem. When you are plugged into shore power your Earth connection is connected to any other boat that's plugged in, as well as any marina structure that's Earthed. If your Earth is connected to the anode your anode is therefore connected to the anodes of all of those other boats that are plugged in. If one has depleted anodes are some other issues, your anode won't last long at all, neither will anything the anode was protecting. A GI prevents this from happening (as does an IT).

It is a requirement of the RCD/RCR that the shore power Earth on all new builds be bonded to "the water", commonly done by connecting it to the anode. So a GI/IT is essential to make sure the boat is protected from the issues above. If your boat pre-dates that requirement you may not have that Earth connection and a GI/IT would be a waste of time/money. The OP's boat may also not have that connection, but there is no guarantee, no matter how Princess built it. Equipment could have subsequently fitted that requires the Earth connection, such as an inverter (although you'd hope the electrician that fitted it made the connection and also fitted a GI).

I don't think it's a case of "No galvanic isolator seems to be the Princess thing." i would expect that current models, with the required Earth connection, would have a GI/IT or they leave themselves open to an expensive claim from boat owners. I may be wrong of course, i don't have a new Princess to check.

I think the OP should check for the Earth connection and if present check for the existence of a GI, if there isn't one, get one fitted, they are not expensive.