Onboard Isolation Transformer vs Safety

[Ahmet Erkan]

Originally Posted by transmitterdan

Perhaps the only reason to dislike the isolation configuration, in favor of the polarization configuration, would be if one owned a galvanic isolator factory...

Wait, maybe there is a real reason why a person may dislike the "isolation configuration" :
The "isolation configuration" as shown in ABYC E11 diagrams 6 and 7 is not a proper isolated ground power system and it is not safe for the crew, nor for a diver or swimmer.

USE A GALVANIC ISOLATOR
If the performance of the off the shelf galvanic isolators are not good enough for you, make your own GI (ask me how) so that it is just as good as an IT and has no single point failures, and it allows your ELCI CB to do its job.

Thanks
Ahmet (not a factory owner, just a retired EE trying to help fellow sailors)

[Ahmet Erkan]

Originally Posted by CharlieJ

Post # 163: Wrong answer. An "isolation transformer" wired as you recommend is non-compliant with the ABYC Standard and is not an isolation transformer in that it does not isolate the mains safety ground system from the vessel's safety ground system which is the primary reason for installing an "isolation transformer".
Post # 160: Correct answer.. Couldn't have said it better myself.

What ?
When did I ever recommend how to wire an isolation transformer?
I recommended over and over again to remove the diagrams 6 and 7 from E11 because they are WRONG.

[Ahmet Erkan]

Originally Posted by transmitterdan

Here is a real non-trick question.

Can you provide any example of anyone injured from a system wired per ABYC E11? If not, then explain why there has never been an injury.

As said many times, I do not have statistical data available to me. I can only offer typical failure mode scenarios that you say are not likely. (ie: Using typical NEC verbiage...A crew member accidentally coming in contact with a live conductor of the IT secondary while standing on the hull ground will not trip the ELCI)

Gotta go.
Bye for now.

[Jammer]

Originally Posted by transmitterdan

This thread should be deleted IMO.

I agree.


The problem with this thread is that there is unsafe advice being dispensed under the color of authority.


There is nothing wrong IMO with a respectful discussion of the benefits and drawbacks of alternative wiring approaches. That is not what is going on here. These alternative wiring approaches are being presented as settled best practices rather than the novel, experimental alternatives that they are.

[transmitterdan]

Originally Posted by Ahmet Erkan

As said many times, I do not have statistical data available to me. I can only offer typical failure mode scenarios that you say are not likely. (ie: Using typical NEC verbiage...A crew member accidentally coming in contact with a live conductor of the IT secondary while standing on the hull ground will not trip the ELCI)

Gotta go.
Bye for now.

You made the claim crew will be injured. Please explain what has to happen to injure the crew. I don’t believe there is any plausible scenario where crew will be injured. So the onus is on the one claiming a safety hazard exists to prove that claim. It would really help if it has ever actually happened. Which it hasn’t. Thus the level of proof is extremely high. We have enough real safety issues in boating as it is.

[DotDun]

Originally Posted by Ahmet Erkan

As said many times, I do not have statistical data available to me. I can only offer typical failure mode scenarios that you say are not likely. (ie: Using typical NEC verbiage...A crew member accidentally coming in contact with a live conductor of the IT secondary while standing on the hull ground will not trip the ELCI)

Gotta go.
Bye for now.

You've been told how to protect against your bogeyman. Use an ELCI with open sensor (e.g., Carling PB or LineGuard or similar) and run the boat ground through the sensor.

Since no one has ever seen your bogeyman, you'll most likely have a hard sell at ABYC. This discussion should take place there, not here.

[Adelie]

This thread has been closed due to the ongoing belligerence of the argument and because it appears to just be cycling around the same issues with no end in sight. If you wish to appeal to outside authorities do it outside of CF.

DO NOT RESTART THIS TOPIC ON CRUISERSFORUM.

The moderators express no opinion about the technical merits of any side of this discussion.