Camper_Jeff_&_Kelli wrote:

I am performing a battery test on the TCs new AGMs. I've got four lights and the stereo running to see how the battery charge holds up. I started the test about 10:30 and checked it at 6:30. The voltage on the batteries has gone from 12.8-9 Volts down to 12.5-4 Volts and at 8:30, just now, 12.4 steady volts. I'm waiting to see how long it takes to get the batteries down to 12.2 steady Volts. The stereo is rated to use up to 10 amps so I will call that 5 amps since I'm not actually measuring it but it is turned up a little loud to drive the 4x50W amps more. Four lights are on totaling 8 amps. Total amps being used for the test is about 13 amps. Right now, we are at 13 amps for 10 hours or 130 amp hours of output and the batteries are still at 70% or so. 12.2 volts is considered 60%. The other thing this test will let me do is see if the new Power Max, Boon Docker, 45 amp power supply, when turned back on, will kick into the bulk charge mode at 14.6-7 volts.
UPDATE:
It's 10:00 and the test period is over. The battery was registering 12.4-3 volts so I turned on 4 more lamps, 10 more amps for 00:30 minutes and the battery never registered less than 12.3 volts. At 10:00, I turned off the 4 additional lights and the battery voltage went back up to 12.4 volts. I shut off 3 of the other 4 lights and the stereo leaving only 1 twin tube fluorescent lamp operating at 18 W / 1.4 amps. The battery voltage went up to a stable 12.5 volts after what should be an effective 12 hours @ 13 amps for a total of 156 amp hours of usage. Looking at the battery usage table near the bottom of this page, (Northern Arizona Wind & Sun). After 12 hours of 13 AMP load and using the loaded voltage reading of 12.3 volts, my new SEARS PM-1 AGM batteries never discharged below 70% of full charge according to their table for DOD "Depth of Discharge". When I shut off all the loads, leaving only one fixture operating, the voltage read 12.5 volts or 80-90% of a full charge. I am very impressed by the performance of these batteries.
I plugged the Power Max in after the test was over and the voltage output of the power supply only went to 13.2 volts. The power supply did not kick into the bulk charge mode of 14.6 volts. I guess it didn’t recognize that the batteries had discharged enough to warrant a bulk charge. Now I’m really interested in heading out for a weekend with no shore power for a couple days to see how the whole system works with the 4 gauge wiring upgrade to the truck alternator for charging purposes and the solar panels contribution which today was for about 2 hours was measured at 1 amp @ 14.2 volts or 14.2 watts.

While this test is running, I did my weekly walk around the TC. After lots of rain the last couple days I discovered the rear left side exterior compartment had wetness. I looked around for a source but could find no obvious cause. I did notice the putty seal for the TC left rear tail light looked dry and brittle so I removed the fixture. There it was, totally wet inside. I scraped off all the old putty and installed new putty. I also caulked the top and sides of the tail light fixture to further seal it, leaving the bottom un-caulked to allow an escape route for water. It will be a couple days of drying to verify if this fixed the problem or not. I did scrape and caulk a couple suspicious places with the edge metal strip too while I was at it.

JoeChiOhki wrote:



If yer steady voltage was at 12.5, the system still thinks yer batteries are at around 85-90% of charge (12.6+ is considered full charge on a wet cell) and went to the appropriate charging state which likely in the design is 13.2 to prevent excess boiling.

Drawn down to a steady voltage of 12.3, mine goes up to the next stage of 13.71 volts, however, the batteries are also cold so their current movement is down as well as it's possible to still be near the batteries available capacity when its core temp is around 40 degrees with a lower voltage.