Diode failure

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KAM

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Had the diode on the domestic supply on my Stirling 70 amp split charge diode box fail a couple of days ago. I only noticed it when I saw the starter battery charge volts shot up to 16.5 volts. Fortunately I had accidentally bought a 3 battery diode and was able to swap to the spare and get back in action. I was just wondering why the starter battery charge voltage jumped to 16.5 and if there was any warning device I could fit.
 
KAM said:
Had the diode on the domestic supply on my Stirling 70 amp split charge diode box fail a couple of days ago. I only noticed it when I saw the starter battery charge volts shot up to 16.5 volts. Fortunately I had accidentally bought a 3 battery diode and was able to swap to the spare and get back in action. I was just wondering why the starter battery charge voltage jumped to 16.5 and if there was any warning device I could fit.
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My first guess is that your alternator/ Sterling regulator has battery sensing connected to the domestic battery When the diode failed the alternator went to max volt output in a futile attempt to get the volts on the domestic battery up to its normal charging figure.

I dont know of a warning device but it is something I'd expect any electronics geek to be able to put together in a few minutes.

I'd be wondering why the diode failed
 
Yes of course thanks for that. It's the second one I've had fail in 10 years. Maybe it's a bit overloaded if I use the anchor winch just after starting the engine. It's a 70 amp diode. Not sure how they are rated. I have an 80 amp alternator but I've never seen the output go over 45 amps.
It's got a smart controller fitted as well which probably makes it worse.
 
VicS said:
My first guess is that your alternator/ Sterling regulator has battery sensing connected to the domestic battery When the diode failed the alternator went to max volt output in a futile attempt to get the volts on the domestic battery up to its normal charging figure.
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Almost certainly. The same thing happened many years ago on a Broads cruiser owned by my parents. I'd put an Adverc booster on it, and when the diode died the Adverc pushed 17v or so into the start battery, which literally boiled dry. My parents had wondered what the funny smell was...

Having a 3-battery diode splitter and wiring 2 legs to the domestic batteries gives some degree of protection if one diode blows.
 
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Yes mine has an adverc too. Seems a bit of an unsatisfactory situation. Needs an alarm.
 
KAM said:
Yes mine has an adverc too. Seems a bit of an unsatisfactory situation. Needs an alarm.
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Fit a battery monitor, the Victron one has low and high voltage alarms.

If you are changing the diode i'd fit a Victron ArgoFET, no wiring changes needed to fit one. Slightly more money than a diode, but you lose the voltage drop, which might mean you longer need the Adverc, depending what your alternator puts out without it, as Advercs were often fitted to overcome the voltage losses associated with diodes. Either way, the ArgoFET would be my choice of replacement.
 
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PaulRainbow said:
Fit a battery monitor, the Victron one has low and high voltage alarms.

If you are changing the diode i'd fit a Victron ArgoFET, no wiring changes needed to fit one. Slightly more money than a diode, but you lose the voltage drop, which might mean you longer need the Adverc, depending what your alternator puts out without it, as Advercs were often fitted to overcome the voltage losses associated with diodes. Either way, the ArgoFET would be my choice of replacement.
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Other makes available as they say on the telly.
 
PaulRainbow said:
Fit a battery monitor, the Victron one has low and high voltage alarms.

If you are changing the diode i'd fit a Victron ArgoFET, no wiring changes needed to fit one. Slightly more money than a diode, but you lose the voltage drop, which might mean you longer need the Adverc, depending what your alternator puts out without it, as Advercs were often fitted to overcome the voltage losses associated with diodes. Either way, the ArgoFET would be my choice of replacement.
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A FET drops voltage as well, less than a diode, but depending on the spec and current passing through, it can be 0.3 volt, hence the zero volt drop is spec'd is at float charge not 100 amp.

Brian
 
halcyon said:
A FET drops voltage as well, less than a diode, but depending on the spec and current passing through, it can be 0.3 volt, hence the zero volt drop is spec'd is at float charge not 100 amp.

Brian
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Yes, i'm aware there is a small voltage drop, Victron do not claim theirs to be zero drop, unlike some. They do, however, have a place. Some installations are well served by a simple VSR, others may be better off with something like an ArgoFET, then again, others require alternative solutions. It depends not only one the boat, but how it is used.
 
PaulRainbow said:
Of course there are other makes, everyone here knows that. I'd still fit a Victron one though.

There are lots of telly quotes, i like Anne Robinsons catch phrase.
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Was having a conversation with the leccy from a yard that produces low volume very expensive craft a while ago concerning out of box failures and the difficulties of manufacturers policies for addressing said malfunctions. Some fare distinctly better than others.
 
third engines said:
Was having a conversation with the leccy from a yard that produces low volume very expensive craft a while ago concerning out of box failures and the difficulties of manufacturers policies for addressing said malfunctions. Some fare distinctly better than others.
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No doubt the same in all industries. I've fitted a lot of Victron stuff and <touch wood> never had an out of box failure yet. I deal directly with the largest stockist/importer of Victron products in the UK, who also supply the likes of Fairline, Sunseeker, Princess etc. All of the Victron equipment that i supply carries a 5 year warranty (except batteries).
 
Alternatively OP might like to redesign the system to fit a VSR. The anchor winch would then operate directly from engine battery so hard wired to the alternator output. The sensing for the alternator would also go directly to the engine battery. So much less chance of over voltage. olewill
 
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