I just installed a new alternator and upgraded it from 51amp to 90 amp. The Alternator chargers my lead acid starter battery and I have the Orion-tr Smart Isolated 12-30 DC-DC charger charging the LIFEPO4 house bank from the Starter Battery/Alternator. This worked fine with the 51amp alternator. However with the new alternator when the DC-DC charger senses the Alternator and turns on, I lose my tachometer within 5 seconds. If I manually shut down the DC-DC charger, the tachometer returns. The Tachometer wire is attached to the AC terminal on the alternator. The new alternator is an internally excited alternator and the older one was externally excited. Any ideas what may be causing this interruption in the Tachometer signal? The alternator appears to be otherwise functioning as expected as does the DC-DC charger.
