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question regarding changing house batteries.

Posted: September 29th, 2021, 2:42 pm
by sm350bl
Sorry if this is redundant information, I searched and couldn't find an answer. I am going to replace my house batteries and I swear I read somewhere somebody had mentioned a specific order in which to unhook and re attach the battery cables pertaining to the low voltage warning unit, like unhook negative first then positive and vice versa. I usually unhook neg first then positive and re-attach positive first then neg. Does anybody recall if there is a specific order to protect the low voltage warning unit or does it not really matter?

Re: question regarding changing house batteries.

Posted: September 29th, 2021, 5:27 pm
by sm350bl
Well, swapped in my group 31s in place of the old tired group 24s. Now the house batteries dont charge with the generator, they do charge with the van running though. Is this a magnetech problem? I checked the distribution panel under the sink, all the breakers were good.

Re: question regarding changing house batteries.

Posted: September 29th, 2021, 6:23 pm
by sm350bl
30amp circuit breaker on base of generator stand was kicked off. switched that back to the ON position and everything started functioning again.

Re: question regarding changing house batteries.

Posted: September 29th, 2021, 8:18 pm
by chin_k
Unless I have been doing it wrong all these years, but I usually remove the negative terminal connection first, taking care not to touch the positive terminal or any wire connected to it. Once the battery is disconnected from the chassis ground, there is no worry about spark/welding/shock when you remove the positive terminal connection.

When connect the battery back, do it in the reverse order. Connect the positive one first, then the negative. Make sure there is minimum load on it (that is, shut off all the DC appliance if possible), so that there will be minimum current when you connect the last connection (negative terminal to ground).

Re: question regarding changing house batteries.

Posted: September 30th, 2021, 1:20 pm
by sm350bl
That is standard procedure as well as I know too. That is what I end up doing. I thought I had read something awhile back that seemed counter intuitive and I told myself to remember if I go to change the house batteries. I was doing this at my work after hours so I was on a somewhat time constraint. When the new batteries weren't charging off the generator like they were literally 20 min before the big alarm in my head started going off " You are deviating from the repair schedule!" and kinda threw me in a tizzy. But I was able to find that circuit breaker on the genset and ultimately still got my batteries replaced and did a full service on the generator, oil, air filter, spark plug.

Re: question regarding changing house batteries.

Posted: September 30th, 2021, 2:57 pm
by chin_k
If I read something weird or unusual, I ask questions. Exception is rare, and they usually involve some logical explanation. It probably makes me sound dumb, but someone will learn something.