Help: Need a wiring diagram

[bhays-SKO]

I need to charge the main bus batteries (2) and a deep cycle in the rear from the bus alternators or from a gas powered 12vd generator I put together with a honda motor and an alternator. Here's how it should work:

- When bus is running: alternator should charge both front and rear batteries
- When Generator is running: it should charge the batteries
- If generator nor bus running: isolator should protect main batteries from being run down.

I am unsure what needs to go to chassis ground, vs negative battery terminal, etc. Can someone connect the dots for me?



Here's the manual for the battery isolator: http://www.abt.com/documents/39744/PAC200_manual.pdf

And here is the diagram for the stereo system, if anyone needs to see that:


Thanks in advance. I was hoping to finish this wiring tonight.

 

[TheRainbowBoxer]

Assuming the alternator and generator would play well together, I would set it up like the schematic below. If there is an issue with the generator not being isolated from the alternator, you would need another isolator.

 

[bansil]

Here is another route,lots of ways to use solinoids some controlled by oil pressure switch etchttp://www.expeditionportal.com/forum/threads/59631-Battery-isolator-installation

 

[chev49]

don't forget you can buy normally ON soliniods as well.

 

[bhays-SKO]

Assuming the alternator and generator would play well together, I would set it up like the schematic below. If there is an issue with the generator not being isolated from the alternator, you would need another isolator.[/quote

Do you see any problem wherein the generator would backfeed or cause problems with the alternator? (in reality it's just two alternators. One is on the bus engine, the other on a small gas engine)

Also, the switch you show on the ground side of the isolator, is that necessary? My intent was that any time the generator or bus alternator was providing power, the system would be open to all 3 batteries.

Thanks!!

 

[TheRainbowBoxer]

The problem with setting up the system so it intelligently knows the alt or gen is running will require a way to isolate this input from the batteries' voltage. This will involve more components (2 diodes) then you listed and be more complicated. In the setup below you would need to take the switch out of the ground side of the relay and hook the "relay disconnect" lead from the alt and gen to the other side of the isolator's relay.

*Edited to add* I can't think of any reason the alternators would not work together... but I have never set something like that up, so YMMV.

 

[bhays-SKO]

The problem with setting up the system so it intelligently knows the alt or gen is running will require a way to isolate this input from the batteries' voltage. This will involve more components (2 diodes) then you listed and be more complicated. In the setup below you would need to take the switch out of the ground side of the relay and hook the "relay disconnect" lead from the alt and gen to the other side of the isolator's relay.

*Edited to add* I can't think of any reason the alternators would not work together... but I have never set something like that up, so YMMV.

Any specific value on the diodes?

 

[TheRainbowBoxer]

The information provided for the battery isolator/relay shows that the relay coil pulls less than 1 amp. I would say that a 1 amp diode would probably withstand the power necessary.

 

[TheRainbowBoxer]

I was just re-examining the schematic I posted and saw a backfeed problem... The truck batteries will feed back and keep the isolator connected... Grrr. I think you will need to use a manual disconnect like the first schematic. Sorry for the oversight.