battery isolater

[BrianK]

Can anyone tell me how these things work this one came from a motor home that we took apart.

[DanOpto]

Battery isolators are often just big diodes that block the engine battery current from flowing back into the RV battery side of the circuit.

This keeps power in the engine battery to start and run the engine if the RV side runs the battery down overnight.

When the engine starts, both batteries charge but they cannot discharge back and forth between each side of the circuit.

The diodes do not improve charging or increase power in any way. They actually rob 1/2 volt from you from the voltage drop across the diode.

[BrianK]

So i guess that it would be good for my wrecker to use for a extra battery for jumping cars and such.

   

[whatsnext]

My old Clark motorhome had a solenoid as the battery isolator. Whenever the alternator was not charging it would seperate the two banks. I always wondered what would happen if the solenoid failed and stayed open or closed but I never found out.

JG

[BrianK]

that might be what this is it had two wires coming from the alternater

   

[tecker]

   Isolation from other power producing devices as well as devices with back emf the is not sucked up by the battery.

[whatsnext]

Mine made a fairly loud clicking sound when you keyed the ignition to 'on' and then a releasing spring sound when you shut the key 'off'. It used a firewall mounted starting solenoid. My dad used to call them Model T solenoids but I used to use them for running my rally lights. Very reliable.

John.........