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I am getting some interesting readings from the battery monitors I installed earlier in the year, and trying to figure out the specific problem. I am leaning toward battery issues, but am unsure if I am missing something. The story is this:
My trailer just got back from an eight week visit to a local Rv service center. They were helping me to confirm that my trailer had two bent axles.I might get into this issue in more detail with another thread. The electrical system was working fine when I took the trailer in. I got it back yesterday with two new axles installed including new brakes and springs with a new breakaway switch installed. The battery bank in use, one of two separate battery banks, was reading 0 Ahrs and 0% battery left. The bank is made up of two 6V 210 Ahr flooded lead acid batteries. I measured the volts of the bank at 11.8 volts. This is the bottom limit I set on the battery monitor. The second bank read 97% available. With this information, I charged both banks up to 100%. Each bank was taking in 0.33 amps from the converter/charger when they were filled. This seems to be the residual energy use on the trailer. So far things were going good. Because of an experience I had last year with a long term service stay, three months, I decided to run the "repair" function on my stand alone battery charger. I only did this to the bank that was run down. This seemed to work fine. Two hours later I came back and found one of the battery monitors showed that there were 90+ amps being drawn from the battery bank that had been run down. Nothing in the trailer should be using this much power. The extreme power usage lasted for awhile but gradually came down to 40 amps over 15 or 20 minutes. I checked the wiring around the batteries and the batteries themselves and nothing was feeling hot. I also checked the batteries with a hydrometer. It was reading a little low about 1250. I then unplugged the main cord to the trailer which would turn off the converter/charger. When I went back to the battery monitor it showed a draw of 147 amps. All of this with the voltage reading 13.1 volts steadily and the Ahrs going down rather rapidly. With this I disconnected the batteries. I then switched over the battery banks to my second bank. It was reading normally and continued to do so through the night maintaining a reading of a 0.36 amps draw.
Because the second battery bank has worked as normal, I think that the main components of the electrical system are working fine. I should note that the two battery banks are separated by a switch with only the batteries and battery monitor shunts that are not in common. On each of the two batteries in the bank that were quickly discharging themselves, one cell is reading good and two cells are reading as partially charged with the hydrometer. None of them read totally discharged. I am thinking that there may be a problem in one or both of these batteries.
Not sure where to go from here. I could just replace the batteries that seem to be having an issue. Is it possible that there is a problem with one of the two battery monitors? BTW both of the battery banks worked fine and all of the battery cells read fully charged before the repair trip.
Norm
My trailer just got back from an eight week visit to a local Rv service center. They were helping me to confirm that my trailer had two bent axles.I might get into this issue in more detail with another thread. The electrical system was working fine when I took the trailer in. I got it back yesterday with two new axles installed including new brakes and springs with a new breakaway switch installed. The battery bank in use, one of two separate battery banks, was reading 0 Ahrs and 0% battery left. The bank is made up of two 6V 210 Ahr flooded lead acid batteries. I measured the volts of the bank at 11.8 volts. This is the bottom limit I set on the battery monitor. The second bank read 97% available. With this information, I charged both banks up to 100%. Each bank was taking in 0.33 amps from the converter/charger when they were filled. This seems to be the residual energy use on the trailer. So far things were going good. Because of an experience I had last year with a long term service stay, three months, I decided to run the "repair" function on my stand alone battery charger. I only did this to the bank that was run down. This seemed to work fine. Two hours later I came back and found one of the battery monitors showed that there were 90+ amps being drawn from the battery bank that had been run down. Nothing in the trailer should be using this much power. The extreme power usage lasted for awhile but gradually came down to 40 amps over 15 or 20 minutes. I checked the wiring around the batteries and the batteries themselves and nothing was feeling hot. I also checked the batteries with a hydrometer. It was reading a little low about 1250. I then unplugged the main cord to the trailer which would turn off the converter/charger. When I went back to the battery monitor it showed a draw of 147 amps. All of this with the voltage reading 13.1 volts steadily and the Ahrs going down rather rapidly. With this I disconnected the batteries. I then switched over the battery banks to my second bank. It was reading normally and continued to do so through the night maintaining a reading of a 0.36 amps draw.
Because the second battery bank has worked as normal, I think that the main components of the electrical system are working fine. I should note that the two battery banks are separated by a switch with only the batteries and battery monitor shunts that are not in common. On each of the two batteries in the bank that were quickly discharging themselves, one cell is reading good and two cells are reading as partially charged with the hydrometer. None of them read totally discharged. I am thinking that there may be a problem in one or both of these batteries.
Not sure where to go from here. I could just replace the batteries that seem to be having an issue. Is it possible that there is a problem with one of the two battery monitors? BTW both of the battery banks worked fine and all of the battery cells read fully charged before the repair trip.
Norm
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