Capflyer

Well Known Member
I am confused as to the proper wiring for a dual LSE Plasma II with two batteries and one alternator system. In my wiring, only one battery is being charged by the alternator at a time and the plane is only running on that one battery. If I connect the controllers to only one battery then when I use the other battery it is not connected. If I connect one controller to each battery then still only one of the batteries is being charged and the other is just running the ignition and drawing down the battery.

I have searched for posts and talked to Klaus. No relavent posts and Klaus doesn't seem to want to understand my set-up. The dual power supply drawing that LSE provides doesn't really address my issue as the aux battery in the drawing is just a back-up battery.

Thoughts, drawings, ideas, all happily accepted.

Thanks
 
Mike,

Check with your local marine supplier, this set up is very common in boats. They even make a cool little device that doesn't allow the current to flow from one battery to the other, thus leveling them both at some low figure but allows them both to be charged from the same alternator. They will (should) have a set up which allows both batteries to come on line for starting.
 
Lightspeed has a diagram here.....

Both batteries kept charged, ign B can run off the aux or main battery using the "power select" switch. Up is normal down position is Aux supply.

psdiagram.GIF
 
psdiagram.GIF


I am replacing my one mag with a second Plasma III and connecting a Shorai aux battery as per the above diagram except it will not be charged by the alternator so I will be leaving out the circuit with the 10 amp breaker and the diode. I plan to charge the aux battery once or twice a year from a mains charger.

The above diagram appears to show that the voltmeter will always be on and drawing power even with the engine and master off as it is connected directly to either the main or the aux battery. One way around this is to use a SPDT switch with ON - OFF - ON for the Power select switch with the switch put in the OFF position when the engine is shut down or I could use an extra switch just before the voltmeter.
Anyone got a better idea?

Fin
9A
 
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I am confused as to the proper wiring for a dual LSE Plasma II with two batteries and one alternator system. In my wiring, only one battery is being charged by the alternator at a time and the plane is only running on that one battery. If I connect the controllers to only one battery then when I use the other battery it is not connected. If I connect one controller to each battery then still only one of the batteries is being charged and the other is just running the ignition and drawing down the battery.

I have searched for posts and talked to Klaus. No relavent posts and Klaus doesn't seem to want to understand my set-up. The dual power supply drawing that LSE provides doesn't really address my issue as the aux battery in the drawing is just a back-up battery.

Thoughts, drawings, ideas, all happily accepted.

Thanks

Lightspeed wants a dedicated wire direct from the battery to the ignition switch so you
don't shut off the ignition if you need to shut off the master.

Just run a dedicated wire from each battery to a toggle switch that will choose the battery
that the two ignitions will run from.
 
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