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Re: Battery Charging woes
Thank you for the replies! Don't know the brand/model of the converter. I have manuals for everything in the MH except of course that. I need to dig in there and look at it. I will connect to shore power with batteries disconnected and test voltage, then report back. Battery cables are not backwards. I "feel" like the converter is under charging. As stated it should be 13.6 while charging and it isn't. But I also thought that the converter would either just work or not work. But I suppose that is not the case. It is charging, just not high enough voltage??? Old-Biscuit wrote: What Brand/model of converter/charger do you have (or inverter/charger). The 'charger' output while on shore power or generator is low..... Connect to shore power for a few hours B1 12.6 B2 12.6 Disconnect shore power, connect and run generator B1 12.7 B2 12.67 You are seeing higher voltage when running engine.....but the charge line is small so charging of batteries would take hours. Need to test 'charger' output with battery cables disconnected. With 110V AC power in.....charger output should be 13.6V DC. Anything less 'charger' is not functioning properly. Also check that you didn't connect battery cables backwards and the 'reverse polarity' fuses on converter/charger are blown. If they are blown the charger output can't get to batteries.253Views0likes0CommentsBattery Charging woes
Bought 2 new deep cycle 12V coach batteries in March. We went on a 1 week dry camping trip in July. Ran the generator for probably 2 hours per day on that trip. The batteries steadily discharged to the point where they would not start the generator. Had to start the truck engine to start the generator. We have not been using the MH much but I decided to check in to this yesterday as it bugs me. BTW I always disconnect the coach batteries while the MH sits. Also connect them and start the generator and MH engine every 2 - 3 weeks. I did these "tests" (sorry I don’t think I can use any fancy “formatting”) B1 = under hood coach battery B2 = compartment coach battery T1 = truck battery Static Check Voltage B1 11.43 B2 11.35 T1 12.26 Connect to shore power for a few hours B1 12.6 B2 12.6 Disconnect shore power, connect and run generator B1 12.7 B2 12.67 Turn off generator, run truck engine B1 13.85 B2 13.5 T1 14.76 Ran truck engine for 30 minutes B1 13.3 B2 13.2 T1 14.16 Next morning static voltage B1 11.93 B2 11.94 T1 12.5 I found a table on the net that says State of charge at volts 100% 12.6V+ 90% 12.5 80% 12.42 40% 11.9 So my 2 coach batteries (new in March) after charging yesterday are at 40% and they will drop more. My truck battery seems to stay at about 90%. When connected to shore power or generator power the max “charging” voltage I see is 12.6V. The alternator on the truck engine seems to charge all the batteries at a higher voltage. My truck battery, which is older and NOT deep cycle, holds a charge much better than the 2 coach batteries. Questions: Should the gen or shore power charge at a higher voltage measured at the battery terminals? Is my inverter/converter not doing its job properly? Should it be “letting” the batteries get a bit of an overcharge like the truck alternator does?2.2KViews0likes10Comments
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