Battery charging device conflicts

escapism

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I've recently had to replace the boats pwm solar charge controller as it was only charging one of the two batteries and offering gibberish on its display. The
replacement is working well, but a line in the 'manual' gives pause for thought: "Not to be connected to any other charging source". Well I'm hoping that this means I shouldn't connect the mains charger to the input, but an alternative reading is that it shouldn't be in parallel with other charging sources.

We have/had three charging sources essentially connected permanently in parallel: pwm solar, Dolphin mains charger, Engine alternator. On installation there were problems with the solar and alternator activating the Dolphins fan. Sadly, the introduction of Schottky diodes solved that problem, but meant the charger could no longer sense the battery state. I've now put a double pole relay on the chargers output. However, I don't know how the Dolphin charger or alternator output might affect the solar charger.

So, my question is: should charging sources be isolated from each other?
 

Poey50

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The output of each charging source will be determined only by the relationship between its own charging characteristics and the state of charge of the battery. So they will play nicely together even if one is playing harder than the others.
 

jiris

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I think they mean it shouldn't be used to control charging from other power source, like wind gen etc. I can't see any harm if you start charging the batteries from the alternator or another solar set etc while having the controller on. It monitors the battery voltage and if the other source manages to reach any of the points where the controller should act by reducing the charging current, it will, leaving the control "in the hands" of the other source.
 

VicS

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So, my question is: should charging sources be isolated from each other?
ITYWF the only time youd have trouble is with a controller that uses a shunt type dump resistor as that could try to dump the output from the shorepower charger ( or alternator),
The old ( obsolete ) single battery Aerogen regulator would do that ... the dual output regulator was OK and had to be used where an alternator was also charging the battery.

( Just been reading the Aerogen instructions!)
 
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