Autohelm ST2000+ Terminally Ill?

[Corribee Boy]

I'm afraid my diode didn't stand up to the reverse polarity incident so not that good at blocking! It does seem a bit of a design flaw to have a non user-serviceable thing that vulnerable to a stupid error.

 

[savageseadog]

Yes sorry, looked at the circuit again, I stand corrected. But a bridge would give approximately twice the volt drop.
Mike

Yes

I'm afraid my diode didn't stand up to the reverse polarity incident so not that good at blocking! It does seem a bit of a design flaw to have a non user-serviceable thing that vulnerable to a stupid error.

There are two basic methods of protecting from reverse voltage. One is a diode in series. The other a diode across the power connections with the cathode of the diode to positive, a fuse or breaker will also be necessary as the diode will simply blow or melt the wiring on a reverse connection if it's big enough.

 

[Corribee Boy]

I honestly haven't a clue what happened inside the unit; the service centre didn't actually tell me what they'd had to do. I just thought an external, user-replaceable fuse would be of more use and less likely to cause problems if the incident had happend way out at sea.