Chassis batteries needed charging.

[draboo]

I noticed that the chassis batteries were down to around 12.0 volts. The coach batteries are maintained well thanks to the inverter/charger system. I connected the chassis and coach batteries with a jumper to charge the chassis batteries for two days. I took off the jumper and the chassis batteries were at 13 volts. Now, a day later, they are down to 12.5 V.

Is this a normal voltage drop? Might they need replacing? I thought the inverter charged all the batteries, not just the coach.

Thanks for any info.

Brad
02 Holiday Rambler Neptune 34ft DP

[pianotuna]

Hi,

Seeing as 5 amps is enough to maintain a chassis battery, there really is not much point in doing the amp-l-start. The two devices do work a bit differently. The trik-l-start doesn't do an over voltage protection and the amp-l-start does. Where I live, I want the extra voltage because of extreme low temperature.

The whole idea of both units is to act as a maintainer, not a charger.

I also did not want a beeper going off.

mike brez wrote:

pianotuna wrote:
Hi,

I would add a trik-l-start or amp-l-start. (my personal choice was the trik-l-start).

Just curious why the trik over the amp? I thought through reading the amp is a upgraded trik.

[mike_brez]

pianotuna wrote:
Hi,

I would add a trik-l-start or amp-l-start. (my personal choice was the trik-l-start).

Just curious why the trik over the amp? I thought through reading the amp is a upgraded trik.

[lanerd]

Yes, with all due respect, a drop from 13v (meaning the batteries had just been on a charge cycle and is dropping back down to their normal full charge) to 12.5 is most definitely normal, especially if the batteries) are several years old. The OP's mh is an 02 and he just got the mh 3 months ago, so we really don't know how old his chassis batteries really are.

If the batteries have been charging, then it's important to let the batteries set for 2 to 3 hours without a load or charger connected to stabilize before testing. Otherwise, the reading will be high, caused by a phenomenon called "surface charge"; hence, the reading of 13v.

He measured the voltage immediately after charging to get the 13v then the next day he only had 12.5. So depending upon how old the batteries are and the amount of parasitic load that was present, the drop is definitely normal.

Ron

[Gjac]

draboo wrote:
I noticed that the chassis batteries were down to around 12.0 volts. The coach batteries are maintained well thanks to the inverter/charger system. I connected the chassis and coach batteries with a jumper to charge the chassis batteries for two days. I took off the jumper and the chassis batteries were at 13 volts. Now, a day later, they are down to 12.5 V.

Is this a normal voltage drop? Might they need replacing? I thought the inverter charged all the batteries, not just the coach.

Thanks for any info.

Brad
02 Holiday Rambler Neptune 34ft DP

I have a maintenance free chassis battery also from Walmart. I put a battery disconnect on it and it dropped from 12.6v on Nov 4th to 12.5 v on Dec 31st. House batteries were 12.6 to 12.4v for the same time frame. So no that is not a normal voltage drop for one day. All the batteries are 8 years old. The easiest way to tell if your chassis battery is being charged along with your house batteries when you are plugged in is to check the voltage at the pos and neg terminals and if you see around 14 v it is charging.

[Motor7]

Thanks for the info on the Trik L Start....I just ordered one from rvupgradestore for $35.75 shipped.......;)

[lanerd]

I had a Safari that was probably the same as your Neptune. It did NOT charge the chassis batteries when on shore power. I installed a Trik-l-start and never had another problem with the chassis batteries.

FWIW, 12.5 to 12.6 volts is indication of a full charge. You will only read higher when the batteries are being charged. So going from 13v down to 12.5 is normal when the charger has been turned off. When measuring a battery, turn off the battery disconnect and wait for about a 1/2 hour before measuring.

Purchase and install the Trik-l-start....it will solve your problem.

Ron

[MrWizard]

30 min is not enough charge time
Try six hours with the charger, then let them rest over night and then check them

[pianotuna]

Hi,

I would add a trik-l-start or amp-l-start. (my personal choice was the trik-l-start).

[Coyote74]

If u leave antenna booster on it will pull bat down over time.

[mike_brez]

I wired this in.

[Pass42]

In my coach, the carbon monoxide & propane detectors as well as the steps are wired to the chassis batteries.....as is the engine computer....left alone, my chassis batteries will go flat in 2 -3 weeks from these parasitic loads...

[Ivylog]

Most Monaco's do not charge the engine batteries on shore power. How big/long of a jumper did you use? Many maintenance free batteries have caps, but they are under the hard plastic top and with some pressing with a screw driver they can be found... usually as a set of three.
If you clean the tops you may find some indication of how old they are and if they are Interstate they could be original.
I would disconnect one battery at a time and see if the other by itself will start your rig. I did that is past summer at a rally before the Interstate battery guys came to check my 03 batteries and had decided to not replace them BUT they let me keep my old ones so I replaced them.
PS: they are still going strong in a 24V machine at home.

[ksg5000]

Have you battery load tested - most tire/auto places with test for free. If you don't have Bird system then consider purchasing a Trik L Start - they are inexpensive, easy to install, and will maintain your coach battery.

[accsys]

We have found the Trik-L-Start to be a very good solution to this problem. It connects between the house and starting batteries to provide a charging current to the starting batteries anytime their voltage is less than the house batteries. It will supply up to five amps charging current. It's big brother, the Amp-L-Start, works similarly but supplies up to 15 amps charging current. What's nice is they are install and forget about them. They work as advertised.