How to check battery level

[Dtnations]

I am a new owner of a Jayco Jay Feather 25RB. I have the Jaycommand panel and I can't seem to find anywhere on the panel where you can see the battery level (how much of a charge your battery has left). Any help would be appreciated!

Thank you!

[Thomson]

We don't use the panel very much because we use the phone app. I can turn on and off lights, etc. with that while sitting anywhere. On that app the voltage appears in the upper right corner.

[gypsmjim]

The battery indicator on ours merely shows 1-4 red dots, which is virtually useless. Buy a 12 volt digital battery meter and plug it into your ("cigarette lighter") plug for your TV and it will show voltage +- 0.1 volts. Correlate to a voltage chart and you'
ll have all the info you need to know.

[Dtnations]

Thank you!

[Zenar]

On the main panel where the tanks are, just press the battery option it will show you the same as the tanks.

[Campingfamco]

Question on this. I see in the app the voltage amount, which is something like 13.2, but I don’t see a level. Is the best way to measure the level to understand how many volts there are and that indicates level? Is there a chart that indicates 13.3 being 80% 13 being 68%? Something like that?

[RAurand]

If you look online, you will see that the Battery voltage/discharge charts all vary a little.

State of Charge
Sealed or Flooded Lead Acid battery voltage Gel battery voltage AGM battery voltage
100% 12.70+ 12.85+ 12.80+
75% 12.40 12.65 12.60
50% 12.20 12.35 12.30
25% 12.00 12.00 12.00
0% 11.80 11.80 11.80

[Campingfamco]

Originally Posted by RAurand

If you look online, you will see that the Battery voltage/discharge charts all vary a little.

State of Charge
Sealed or Flooded Lead Acid battery voltage Gel battery voltage AGM battery voltage
100% 12.70+ 12.85+ 12.80+
75% 12.40 12.65 12.60
50% 12.20 12.35 12.30
25% 12.00 12.00 12.00
0% 11.80 11.80 11.80

Okay this makes total sense then. So we won’t see anything on the JAYCOMMAND app that shows the percent left, just something that shows the voltage. I just want to make sure everything is hooked up properly since I’m seeing some strange activity.

[Jagiven]

Originally Posted by RAurand

If you look online, you will see that the Battery voltage/discharge charts all vary a little.

State of Charge
Sealed or Flooded Lead Acid battery voltage Gel battery voltage AGM battery voltage
100% 12.70+ 12.85+ 12.80+
75% 12.40 12.65 12.60
50% 12.20 12.35 12.30
25% 12.00 12.00 12.00
0% 11.80 11.80 11.80

I have been using a different chart for many years to indicate lead acid charge status. It has been too long since I found this data. Wonder which one is correct??

[gypsmjim]

Originally Posted by Jagiven

I have been using a different chart for many years to indicate lead acid charge status. It has been to long since I found this data. Wonder which one is correct??

Attachment 67945

Your colorful chart is the one I also use. There are many like it and all are relatively close. If you are using a gel or AGM battery, you need to research that.

I can tell you for an absolute certainty that 12.0 volts will start a car engine, but 11.8 won't turn it over. And if you get below 12.2 volts you better get it charged up soon or you will shorten the life of the battery.

[sciencenerd]

Originally Posted by Jagiven

I have been using a different chart for many years to indicate lead acid charge status. It has been too long since I found this data. Wonder which one is correct??

Attachment 67945

This chart is a good starting point.

However, it is only correct when you measure the voltage close to, or better, at the battery, and if there is no load on the battery.

Here is a graph that shows voltage vs. discharge rate:



At C/100 load, the 12.5 V threshold is 50% discharge (in this graph). However, at a moderate C/20 discharge rate, the battery is only 30% discharged at 12.5 V, you can go down to 12.3 V to be at 50% discharge. Under normal conditions, the battery is seldom at rest.

Therefore, the voltage is a very much non-perfect measure for the state of discharge. Much better would be to use an Amp meter, so you know exactly how much charge has been removed form the battery.

[DocBrown]

Originally Posted by gypsmjim

I can tell you for an absolute certainty that 12.0 volts will start a car engine, but 11.8 won't turn it over.

And anything below 12.6 in a modern vehicle (past 10 years or so) will not properly power the computer system and all the sensors. It's one of the reasons they've been moving to 48 volt systems.

[gypsmjim]

Originally Posted by DocBrown

And anything below 12.6 in a modern vehicle (past 10 years or so) will not properly power the computer system and all the sensors. It's one of the reasons they've been moving to 48 volt systems.

I'm an old fart and so are my cars. My 11.8 and 12.0 volt data scenario were with vehicles that were not computerized.

Having said that, my wife's car (she's a young fart) is a computerized 2017 Chevy Traverse. There were battery issues because of a problem beyond our control, causing the battery to drain. The voltage went low, causing the idiot light to illuminate. Naturally, I checked what it was - about 12.2. Knowing there was an issue, I took it to the dealer and had the problem corrected under warranty.

Nevertheless, it started up just fine and the charging system continued to increase the voltage, as it should. So, the 12.6 number aint so. In fact, 12.6 is 100% charged, so if that was absolutely needed all the time, we'd be in a whole pile of ****.

[Quantum]

I installed a USB charging port on my side of the bed. It has a built in voltage readout.

[Jayco224BHW]

Originally Posted by gypsmjim

The battery indicator on ours merely shows 1-4 red dots, which is virtually useless. Buy a 12 volt digital battery meter and plug it into your ("cigarette lighter") plug for your TV and it will show voltage +- 0.1 volts. Correlate to a voltage chart and you'
ll have all the info you need to know.

Greta advice thanks.

Those four dots. Those don't take into account the 50% rule. So if you want to stay above 50% don't let the dots go to 1 or 2. ?? Correct.

And order a battery meter... oh wair. The Solar charge controller shows me the current voltage.

So I can simply watch where that falls to and compare to the battery indicator sensor on tank sensor label and inside the solar charge controller. Thanks

[norty1]

Those four lights are not enough to make any decisions other than there is a battery installed.

[Jagiven]

Originally Posted by Quantum

I installed a USB charging port on my side of the bed. It has a built in voltage readout.Attachment 67956

I have not had good luck with the aux volt meter. I bought a few and they were always off by a fair amount when compared to my multimeter.

[GarlicDude]

I put one of these above the monitoring panel:

https://www.amazon.com/DROK-Programm...%2C2681&sr=8-5

[gypsmjim]

Originally Posted by Jayco224BHW

Greta advice thanks.

Those four dots. Those don't take into account the 50% rule. So if you want to stay above 50% don't let the dots go to 1 or 2. ?? Correct.

And order a battery meter... oh wair. The Solar charge controller shows me the current voltage.

So I can simply watch where that falls to and compare to the battery indicator sensor on tank sensor label and inside the solar charge controller. Thanks

My plug-in voltage meter was not one of the cheap ones. It agrees with my multi-meter.

OTOH, the solar charge controller does NOT agree. Apparently, it does not read battery charge, but something to do with the solar system. I'm not an electrician, so I can't accurately explain what I just said, but the TS person at Renogy told me to not use that meter for the intended purpose.