Alternator Charging of MH House Batts, Ineffective Control
Forest River is putting a Precision Circuits Inc. "Battery Isolation Manager" in at least some lines of its MH's, including my Sunseeker.
Please look at this 2 page PDF about the product. Note item 5c, where they explain that to prevent overcharging house batteries, they turn the charging off after an hour. Then it will only re-start charging if the house batteries fall below 12.6v (that parameter is given on another document and the company verified that to me).
Look at Feature 5.c.
If you have camped off grid, and hope to get a good charge while you drive a few hours, this is no way to charge house batteries. The one hour charge is a problem, and so is the requirement that the batteries show <12.6v. One morning I left Quartzsite, with a good drive ahead of me. My batteries were in serious need of charging. I have solar on the roof, but the sun was so low in the sky that morning that they were not going to produce much. But they produce voltage, so that kept the BIM relay turned off. OK, I shut off the solar. Now I drive 10 minutes to the gas station. In that time, the batteries take on a surface charge. When I leave the station, the batteries are not getting charged. A ways down the road, the house voltage gauge jumps up to 14 something, and it's working. A while later (an hour, I suppose), it's back to 12 something. We stop at a post office, start again, still not charging. Etc.
Am I correct in saying this is a poor logic process? What logic is used by the Intellitec systems? Or others you are aware of? I expect that as long as my house batteries will accept charging, they should be getting it. Am I wrong about that?
Also, in the presence of solar charging, will other isolation systems shut off the alternator charging?
Don't misunderstand, my main point is not about solar. That's just an extra problem here.
Thanks.
Please look at this 2 page PDF about the product. Note item 5c, where they explain that to prevent overcharging house batteries, they turn the charging off after an hour. Then it will only re-start charging if the house batteries fall below 12.6v (that parameter is given on another document and the company verified that to me).
Look at Feature 5.c.
If you have camped off grid, and hope to get a good charge while you drive a few hours, this is no way to charge house batteries. The one hour charge is a problem, and so is the requirement that the batteries show <12.6v. One morning I left Quartzsite, with a good drive ahead of me. My batteries were in serious need of charging. I have solar on the roof, but the sun was so low in the sky that morning that they were not going to produce much. But they produce voltage, so that kept the BIM relay turned off. OK, I shut off the solar. Now I drive 10 minutes to the gas station. In that time, the batteries take on a surface charge. When I leave the station, the batteries are not getting charged. A ways down the road, the house voltage gauge jumps up to 14 something, and it's working. A while later (an hour, I suppose), it's back to 12 something. We stop at a post office, start again, still not charging. Etc.
Am I correct in saying this is a poor logic process? What logic is used by the Intellitec systems? Or others you are aware of? I expect that as long as my house batteries will accept charging, they should be getting it. Am I wrong about that?
Also, in the presence of solar charging, will other isolation systems shut off the alternator charging?
Don't misunderstand, my main point is not about solar. That's just an extra problem here.
Thanks.
