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Topic: Battery/Charging System Faults (Read 501 times) previous topic - next topic

Battery/Charging System Faults

Over the holidays I left my coach in storage, plugged into what is normally good, clean power (30 amp), and with Aquahot electric heaters both on, with coach zones set to furnace heat (60degrees). Normally this works great and keeps my coach warm and cozy when it gets cold outside. At some point, must have lost power, and when it came back on, coach electrical did not reset to provide power, run heating systems, and recharge batteries.
On my next visit to the coach, coach batteries appeared to be fully depleted, although there were two good legs of power available and indicating 120/125 volts (but not being accepted). Could not turn on lights and nothing happened when I pressed the Xanbus SCP Function button.
I went forward and turned on the Boost switch to connect both battery systems together, regained power on the coach system, lights worked, and the SCP now was working again. Function button now working normally. There was a fault indicated so I pressed the Fault Clear button, and system ops appeared to return to normal. System accepted the good power being supplied and began charging batteries.
During this first charging cycle, the batteries were charging at a very high rate - 141A and more, with a 22-24A load on the AC In. Numbers were the same in both Bulk and Absorption mode. Ultimately, the system experienced another fault - DC Over Voltage. This is likely what happened to begin with but I was unable to see it when I first restarted the system. I reset the fault again and left the coach to run some  errands and came back 2 or 3 hours later to find the same DC Over Voltage fault condition. I reset the system again last night about 10pm and left it again with a high charge rate. I had turned off all system heating components since overnight temps were only to be in high 20's for a few hours.
Went back this morning and it was in fault again. When I reset it this time, the charge rate was down in the 40-60A range, AC In was 6-8A range. Going out of town for a couple of days now so hopefully it will stay on line. We'll see.

Question #1: Why wouldn't the system have reset when the power came back on initially. I don't know how long it was off, but I'm checking with the storage unit owner. It's in my neighborhood and I wasn't aware of any power outages. Did I just overload the system with both Aquahot heaters on and all 3 zones turned on?

Question #2: Have I ruined the coach batteries?  They were all replaced Nov 2018.

Thanks for sharing your expertise.

Re: Battery/Charging System Faults

Reply #1 –
If power was off long enough to drop the batteries below 11 VDC or so, the smart charger/smart inverter/charger will NOT attempt to recharge.

This is a good safety precaution, as a continuing to charge a battery, with for example a bad cell could lead to severe overheating, excessive hydrogen production, etc.

Have you materially shortened their life.  You will have to fully recharge them and then load test them to see to what degree they can be resurrected.

Re: Battery/Charging System Faults

Reply #2 –
Year of coach?

It's a good idea to add a signature via your profile so this info appears at the bottom of posts.  Makes it easier for folks to target the answers.
 

Re: Battery/Charging System Faults

Reply #3 –
Quote from: wolfe10 –
If power was off long enough to drop the batteries below 11 VDC or so, the smart charger/smart inverter/charger will NOT attempt to recharge.

This is a good safety precaution, as a continuing to charge a battery, with for example a bad cell could lead to severe overheating, excessive hydrogen production, etc.

Have you materially shortened their life.  You will have to fully recharge them and then load test them to see to what degree they can be resurrected.

Thanks Brett, battery checks on the list.