Charging Problem?

[JRMunn]

I thought about titling this “what now” but decided that my first reaction wasn’t descriptive enough. Can anyone tell me what is going on before I get a new power converter and/or transfer switch? When I returned to my 2004 Sunnybrook 5th wheel after 4 or 5 days, I found that the refrigerator (running on LP gas) had stopped working (ice melted), the light I turned on was dim, and the tank/battery panel indicated “poor” battery condition. The trailer had been left with the refrigerator on before without this problem. I started a generator to charge batteries and heard several clicks. This was a new sound, so I began looking for it. The clicks seemed to be coming from the transfer switch and the power converter was cycling. One click, and the power converter started (and I could hear the generator work harder), about 5 seconds later there was another click and the power converter fan stopped. This was repeated after about 10 to 15 seconds. Meanwhile, the AC system (plugs, TV, microwave, etc.) seemed to be working fine and the 12 volt lights were bright. So the generator was working and power was getting from the generator to the lights. I let the generator run for about ½ hour without apparent improvement in the battery charge condition. The clicking stopped when I put in charged up batteries, so I thought maybe one of the two original batteries had gone bad. I put them on a charger at home, and both were low, with identical 11.9 volt readings. They each took several hours to recharge, starting at 24.9 amps then declining to a float charge at a little more than 13 volts. They both held this charge for more than a day, so the problem is not a dead battery. My only guess is that the power converter isn’t able to recharge the batteries when they get this low. I have two 100+ amp-hour deep cycle 12 volt batteries connected in parallel (for 200+ amp-hours of 12 volt power), an IOTA ITS-30R transfer switch, and an INTELI POWER 9100 Model No. PD9160A power converter connected to a Charge Wizard to prevent overcharging.

JRMunn

[JRMunn]

To all - Thank you for help and advice on something that is new to me. I will try a 50 amp auto-reset breaker assuming that problem with factory 30 amp is greater recharge demand from the two large deep-cycle batteries that I am using. I am not sure whether the breaker is a safety feature for the batteries, the converter, or both. But it must be there for a reason since the manufacture spent the money to put it in.

JRMunn

[time2roll]

As long as you have #8 wire and I believe you should have #6 wire to the battery it would be fine to replace that junk circuit breaker with a proper breaker or fuse rated 60 to 75 amps.

If the breaker is in the middle of the wire just remove it. You have main fuses at the 12v panel and should have some type of fuse at the battery. This middle of the wire breaker is just trouble.

If you want a breaker I recommend a Bussman High-Amp. (manual reset) amazon has it

Or an inline fuse holder similar to maxi-fuse-inline-fuse-holder-w-6-awg-leads-up-to-60a

In the mean time get a charger on those batteries asap.

Were you connected to utility power when all this happened? If so you could have another issue.

[JRMunn]

JK - Wire size from converter (which can put out 60 amps) to breaker and then breaker to battery is same size as battery cable, so the wire can easily carry 50 amps. I don't know why the factory breaker was 30 amps, but I had to work to fit two larger, deep cycle batteries into the battery enclosure, so the original design was for either a single battery or two smaller batteries.

JRMunn

[jkwilson]

Breakers are generally chosen for the wire size that they are protecting. Going to a larger breaker defeats the purpose and creates a fire risk.

That said, it’s not impossible that a smaller breaker than what the wire can handle was used. You’ll have to look at the wiring and determine an appropriate breaker or upgrade the wiring to handle a larger breaker.

Is the breaker a factory part? Seemsodd that the output of your converter is protected at a lower current than the converter can provide. When the batteries get low enough, the converter is going to try to send enough current to charge them and you’ll see just what you are seeing.

[JRMunn]

Scott, you were right about the breaker. I was at the trailer and found a 30 amp automotive type breaker between the converter and the batteries. It was just above the transfer switch. I took it out, and printed on the side was "BUSS CBC-30B 12V J38 30A".

My next question for you or whomever might have an answer is whether it is okay to replace the 30 amp breaker between the converter and batteries with a 50 amp breaker? My trailer has a 30 amp system, and the main 120 volt system breaker has never tripped (even on shore power). So I am surprised that my 2800 watt Yamaha Generator has the power to trip a 30 amp breaker, but my understanding of how this works between the 120 volt generator and the converter's 12 volt battery charger is pretty limited.

JRMunn

[JRMunn]

Scott,

This makes sense, and I should have recognized the sound. My converter will put out up to 60 amps if batteries will take it, so a pair of deeply discharged, large batteries could be tripping a breaker. I guess the next step is to find the breaker and figure out what size it is.

JRMunn

[ScottG]

There is an auto-resetting DC breaker between the converter and the battery that is tripping. It may be truly overloading or just weak from age or corrosion.
Follow the clicking to find it.

It could also be that your battery has shorted internally and is causing the overload.