Battery isolator

This is not entirely accurate. Many RV manufacturers continue to use "diode" based isolator, but yes, they do have a significant voltage drop. The "diode" style isolators are being obsoleted by MOSFET-based isolators where the MOSFETS (semiconductors) behave just like large, high current diodes, but have an insignificant voltage drop my magnitudes of efficiency and some high end motor coach manufactures are migrating to this never technology. There are several companies that offer MOSFET based isolator, but the best I could find was Perfect Switch in California. No affiliation but a super-please customer, FWIW

OnaQuest wrote:

KnowNuthin wrote:
Just recently the starting system on my generator began to act up… Sometimes it would spin just as it should… Other times I would just get a click and maybe a half a turn on the crank…

I've been investigating the electrical system and found that the solenoid type battery isolator in my coach typically doesn't last very long… A few years or so…I'm thinking the isolator that's in there now is the original from the manufacturer...

My question is… On the dash of my motorhome is an auxiliary start switch which I assume ties the two batteries together when activated to assistant starting the coach engine… Do I need a special isolator to keep this feature intact or will any three post battery isolator suffice...so long as the amperage rating is correct...

I'm planning on cleaning all the battery connections and running a separate ground to the generator from the coach frame… Hopefully that will keep the generator starter happy…

There are other reasons that you don't want the diode based isolator, (three post isolator)also. The main reason they are no longer used in large motorhome applications is the inherent voltage loss through the diodes. Your batteries may never receive a proper full charge.

I'd stick with the solenoid based isolator. JMHO