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Old 11-26-2018, 02:20 PM
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Quote:
Originally Posted by ndutton View Post
Joe, whatever went on Bryan was able to isolate it. Remember this passage from the first post of this thread:
I asked about it but did not get a response that I remember, exactly what is this charger he determined to be the problem? From the narrative I think it's an automated charge combiner but whatever it is, it apparently was intermittently dropping the ignition voltage low enough to stop the engine. As I recall the alternator guy recommended a charge management system (battery switch) that did away with the automation and the poltergeist was exorcised.
That still doesn't make much sense. I can see it running the battery down, but then the battery would be down a few minutes later too.

"The few shutdowns that happened in 2017 seemed to happen after approximately 2 hours of motoring. The engine could be restarted and the trips could be completed without further issue. "

There are a few different technologies around. I have an automated combiner relay that replicated a person combing the batteries and then un-combining them. The worst thing it could do would be not work, in which case the battery would eventually go dead or a human would notice and turn the manual switch.
There are DC-DC chargers with various brand names like Echo Charger. They are essentially DC powered battery chargers that aim to supply a start battery with a voltage tailored to it from a big house bank that might have much higher voltages. They are not combiners and do not pass current directly. They have a limited current output like any battery charger. They have a variety of possible failure modes including just flat out not being able to keep up with what the engine systems use. If one became randomly intermittent I suppose it could run the engine battery down, cause the engine to quit, and them spontaneously start working again a little while later. This would be very very obvious if one had a voltmeter.
I never really trusted those things and never installed one without a manual bypass.

Last edited by joe_db; 11-26-2018 at 02:29 PM.
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