The alternator on 93 5.9 cummins in my diesel pusher motorhome puts out a constant 14.6 volts with engine running. When the MH is plugged in the convertor charges at 13.3 volts. Will the 14.6 volts be harmfull to my batteries over time? Will it require a different alternator to fix problem?
Thanks,Rod.

 

14.7 V is the maximum usually recommended so you should be OK with 14.6. The MH converter is for the 12V appliances and likely your deep-cycle camper battery. Your vehicle may even have an isolator to cut the vehicle battery out of the system at a certain voltage so you're engine will start, then your alternator would top the battery off. Lucky you to have that engine in a MH!

 

What is the age and condition of your batteries? I have had similar situations in a truck that had dual batteries. One was loosing a cell and pulling the other down. If you are running a battery isolator the alternator could be sensing the one battery that is going bad and seeing it as a load. Maybe disconnect one battery and see how it acts or get them both load tested.

 

Is the regulator in the alternator or in the computor?

 

In your motor home? Don't know. 92 and 93 trucks have it in the PMC.