430 - 2 electrical issues fuse + corrosion

2 electrical issues fuse + corrosion

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Category: Hints & Tips
Forum Name: 430
Forum Description: 430 Hints and Tips
URL: https://www.myhanse.com/forum_posts.asp?TID=14074
Printed Date: 27 March 2026 at 03:42
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Topic: 2 electrical issues fuse + corrosion

Posted By: rickwheatley
Subject: 2 electrical issues fuse + corrosion
Date Posted: 18 June 2023 at 18:51

Hi all - Wrestling with two electrical issues on my 430e and learning about marine electrical systems along the way. So appreciate any advice in advance!

1. The fuse (100a) that allows the alternator to charge the house batteries (left most fuse on the busbar above the batteries in the photo below) keeps blowing. Anyone with any experience of that? Seems more likely to happen when the windlass has been used (I think but am not sure).. Everything is fine when a new fuse is installed.

2. I was surprised to find that the Yanmar SD50 saildrive had fallen prey to significant corrosion when it was out of the water recently. Following the zincs more closely now and already noticing corrosion. The marina is testing for stray current from the shore power system and other boats.. Nothing yet. I've tested to see how much current is flowing when everything in the boat is powered off - seems to be between ,3 and 1,5 micro-amps which seems well within tolerance? Any tips appreciated! (Next step will be to get a marine electrician aboard)

Appreciate any thoughts!

Replies:

Posted By: Arcadia
Date Posted: 18 June 2023 at 21:26

It seems like the 100 amp fuse may undersized. It is OK when handling only the alternator current, but when an extra high load like the windlass is added, the momentary draw from the alternator may exceed 100 amps. I would think that simply increasing the size to 150 amps will work and certainly not overload any of the wiring.

As far as corrosion goes, it may be best to disconnect shore power once your batteries are charged and you are away from the boat. That will reduce the exposure greatly. I have an isolation transformer in line with the shore power input for good isolation.

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Leon / ARCADIA
2018 Hanse 588
Sag Harbor, NY

Posted By: rickwheatley
Date Posted: 19 June 2023 at 07:42

Thanks for your reply Arcadia - much appreciated!

Agree - increasing the size of the fuse seems like a sensible option. I've purchased a few 150s with that in mind. My hesitance is around whether this would create any new risks I'm unaware of..

The boat has been on shore power too much these past two years so that is a likely culprit - but perhaps not the only? Will research insolation transformers.

Posted By: Ratbasher
Date Posted: 19 June 2023 at 11:38

Rick - the SD50 issue is well known on this forum; the attached advisory from Yanmar might be of interest. I had exactly the same issue despite already having a galvanic isolater and the marine electrician couldn't find any problems. However, 5 coats of epoxy on the saildrive leg and an hull anode added nearby solved the problem completely.

Iain

uploads/5559/MSA2010-007_Saildrive-Corrosion.pdf" rel="nofollow - uploads/5559/MSA2010-007_Saildrive-Corrosion.pdf

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H400 (2008) 'Wight Leopard' Gosport, UK

Posted By: Wild
Date Posted: 19 June 2023 at 19:03

Hello Rick

In the 430 forum page 7 you can find the electric drawings for 430 and a lot more info

Topic :430 drawings & manual online “

Forum: 430

Member: Idelfix Too

Date: 08 September 2012

In the link “ Hanse 430e elschema”

Hope this will help you

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Wild and Wet
Belgium
545e#268

Posted By: rickwheatley
Date Posted: 20 June 2023 at 07:14

Wild - Great collection of material, downloaded - thank you!

Had a copy of that wiring schematic though. Have to admit I'm struggling to find the fuses in the photo though..

Posted By: rickwheatley
Date Posted: 20 June 2023 at 07:28

Thanks Ratbasher - will look at this closely!

Posted By: Wild
Date Posted: 20 June 2023 at 09:06

Yes the diagram is not very clear.

On page 14 They indicated the anchor winch is 75 Amp and protected by a automatic thermal breaker 80 Amp (FAW)( to weak IMO) and not by a ANL FUSE like in your picture. And that’s more logical when it’s blow’s you have to be fast to change ( reload) it.

On page 11 (anchor Winch) thermal breaker 5 Amp (F10P) Nr 11 on the CALIRA panel is only the power for the steering of the anchor winch I believe.

On page 6 from the alternator to the positive buss bar there isn’t a fuse on the wiring diagram so far I can see.

Only the smart battery combiner relais on page 6 (6W4) close to the alternator (24V ???? Mistake ??? of the designer??) and the D+ line go to a relais K1 (Fuse 2Amp) on page 11.

The function of this relais I don’t know for shure maybe the Startassist of the Cyrix combiner? Can’t find it on the drawings.

This is what I can make of this not very clear diagram.

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Wild and Wet
Belgium
545e#268

Posted By: rickwheatley
Date Posted: 20 June 2023 at 10:21

Hey Wild,

Good spotting! I wonder if it could be that the busbar is where I've indicated with the red box on the image of page six below? That would match the layout at least? And given the impact of that blown fuse (alternator no longer charges the service batteries and bow thruster turns on and lowers but lacks the power to deliver thrust) this might make sense?

If correct, odd that these are characterised as switches rather than fuses..