I went out this morning to do the monthly generator run. I like to check all the battery voltages before starting and I noticed that the chassis battery voltage is higher than normal. I verified the BlueSky reading with a multimeter at the battery terminals. The motorhome has been sitting for about a month without running the engine or generator. What might cause this?
Hi Greg; The aux light is lit on the BSE solar controller. It is receiving sunlight from the solar panels. The Auxilliary output was wired by Lazy Daze to provide a trickle charge to keep the chassis battery charged up. It looks high because of so called 'surface charge'. This voltage will drop within seconds to about 12.9 volts if you put a significant load on the chassis battery. A few minutes of headlights should reduce this voltage. Starting the engine would also, but you won't see it because the engine alternator will cover that up. surface charge on lead acid car battery - Google Search (https://www.google.com/search?q=surface+charge+on+lead+acid+car+battery&oq=surface+charge+on+lead+acid+car+battery&gs_lcrp=EgZjaHJvbWUyBggAEEUYOTIHCAEQIRigATIHCAIQIRifBTIHCAMQIRifBTIHCAQQIRifBTIHCAUQIRifBTIHCAYQIRifBTIHCAcQIRifBTIHCAgQIRifBTIHCAkQIRifBdIBCTE2NzAxajBqN6gCALACAA&sourceid=chrome&ie=UTF-8&zx=1770144237904&no_sw_cr=1) It's fine Greg, not to worry! RonB
Appreciate that, Ron. A follow up question: if the chassis battery is left in that high voltage state for a long period of time, could it damage the battery?
Appreciate that, Ron. A follow up question: if the chassis battery is left in that high voltage state for a long period of time, could it damage the battery?
No, that is normal.
Larry
Thanks, Larry.