Battery question

[tbax46]

Two brand new 12v batteries in parallel. The meter on my leveling system shows 12.1 and my handheld tester shows 11.8. Should there be this difference? Have been plugged into 50amp shore power for three days

[garym114]

Plugged into shore power your batteries should be fully charged.

[theoldwizard1]

tbax46 wrote:
The meter on my leveling system shows 12.1 and my handheld tester shows 11.8. Should there be this difference?

To answer this question specifically ...

MAYBE ! First, meters are not perfect. The less expensive they are, the less accurate they are, but two different meters should be within a few tenths of a volt ...

... if you are measuring the voltage at the exact same point! The size and quality of the wiring between two different locations can make a big difference in the reading !

[Njmurvin]

How do you have them cabled? It's better if you have the trailer's load (+) going to one of the batteries and the ground (-) coming off the other.

[edbehnke]

State of Charge batteries
lead gel agm

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

[time2roll]

Less than 13.2 volts while plugged in says your charging system needs looked at.

BTW get a portable charger on those battery asap before they get sulphated while you get the converter sorted out. If spending money get at least 5 amp rated 10+ amps is better.

[Ed_Gee]

tbax46 wrote:
Two brand new 12v batteries in parallel. The meter on my leveling system shows 12.1 and my handheld tester shows 11.8. Should there be this difference? Have been plugged into 50amp shore power for three days

Regarding this voltage reading discrepancy, what are you using for a handheld "tester". Is it a Digital Volt Meter, or something else. Also, are you taking your reading at the battery terminals or somewhere else? If that handheld "tester" has a built in load that it places on the battery when reading the voltage, that could account for the discrepancy in the two readings. ....better off with a DVM in this case. See my other prior post for my assessment of your low battery voltage problem ...

[Ed_Gee]

12.1 VDC indicates a battery already at 50% discharge state. Since you have been plugged into shore power for three days, obviously something is preventing your RV charger from charging the batteries. Do you have a Battery Disconnect switch inadvertently activated? If not, you need to diagnose why the charger is not charging the batteries..... You just installed them? I'd also be suspicious that you did not hook up all the battery cables properly.....maybe you missed one? One thing for sure.....get a charger on those new batteries quickly before they get further discharged and ruined!

[Super_Dave]

My 24's never read 13 anything for the 2 years that I have owned them. High 12's maybe when taken off an independent charger but settles in at the low 12's after a day or 2.

[pianotuna]

Some how the converter is not charging the battery bank. Check the voltage output at the converter.

[joelc]

It is possible one of the meters is off calibration. But I believe 13.6 is correct with no load. I would bring them back where you purchased and have them check with their meter and do a cell check.

[full_mosey]

tbax46 wrote:
Two brand new 12v batteries in parallel. The meter on my leveling system shows 12.1 and my handheld tester shows 11.8. Should there be this difference? Have been plugged into 50amp shore power for three days

You should be reading around 13.6V everywhere after 3 days plugged in. If not, your charging system is either disconnected from the batteries, broken, or not plugged into the 120V system.

Check 12V fuses, the 120V circuit breaker, or a 12V disconnect switch.

HTH;
John

[midnightsadie]

some thing not right new batteries should be over 12.6 ea.

[RobWNY]

Are you unplugging shore power, then waiting several hours so the batteries can rest before testing the voltage using both the RV system and handheld meter?

[Lynnmor]

tbax46 wrote:
Two brand new 12v batteries in parallel. The meter on my leveling system shows 12.1 and my handheld tester shows 11.8. Should there be this difference? Have been plugged into 50amp shore power for three days

What is the voltage at the batteries while plugged in to shore power?