Volts and Dehumidifier

[david1601]

Two questions for those more experienced than me. We just returned from a 3 month trip to the west coast and into Canada. Along the way we did some dry camping for a few days at a time to improve our skills in that department.

My question is... My rig has a 7.5 kw generator which works great but I am still confused about when to run it to charge the batteries. We have a residential fridge. The display shows in volts and charged the batteries are consistently above 12.4.

As the day and night wears on the volts drop as we all know. I would run the generator a couple of hours in the morning and a couple more in the evening. If I could not run the generator at all the volts would drop below 12. Is there a number like 12, 11.8, 11.5 that I should definitely start the generator?

Second question. We purchased a dehumidifier. A really good one for when we are not traveling since we live on the Gulf Coast in a rainy area. I am running it on 40% now. Should it be lower or is 40% good?

[david1601]

beemerphile1 wrote:
Try to not go below 50 percent.

Perfect. Finally something I can understand. Thanks you very much.

[Lwiddis]

“I would run the generator a couple of hours in the morning and a couple more in the evening.“

With the right batteries and an adequate solar system you wouldn’t need to run the generator at all most days. Four hours a day...hate to be camping next to you.

[beemerphile1]

Try to not go below 50 percent.

[time2roll]

Yes end of bulk is fine and up to 1 more hour. Much beyond that amps are tapering off so not as much value for the effort.

[david1601]

I have a 2000 watt Pure Sine Inverter. I am not sure about the charging system. Whatever comes in a 2018 Tiffin I suppose. I am sure it is on the better side.

I have four Duracell Ultra Batteries that came with the coach when we purchased it last year.

I do have auto start but prefer not to use it when camping next to others. The charging voltage will get to 14.4+ volts with the generator running.

I do notice the charging stages. So it is ok to shut down after the bulk charge?

Thanks for the help so far.

[garym114]

Stages of charging wet cell batteries, bulk, adsorption and float.
To reduce gen run time just finish bulk charge, this is about an 80% charge.

[pianotuna]

How much battery capacity do you have? Is that 12.4 under load? (i.e. fridge compressor running)

I'd be tempted to add one of these: https://www.ebay.com/itm/Battery-Monitor-Meter-Wireless-DC-120V-100A-VOLT-AMP-AH-SOC-Remaining-Capac...

[time2roll]

Around 12.2 would be a good time to start the generator. 12.0 would be the lowest. Consider adding an auto-start system.

You did not mention your charging system... does the charging voltage get to 14.4+ volts with the generator running?