Questions for SMB Caretaker

[rt66paul]

For what it is worth, you can buy a solar charge panel that charges(tops off) the battery through the cigarette lighter. If your isolator isn't working correctly, maybe this will charge the battery up enough to see?
These panels were sold with VWs in the 90s and 00s, I got one for less than $20 I use to keep my battery topped off. I see some at Amazon for $25, that charge through the cig lighter, or just buy something with a cig lighter lead and connect it to a battery charger, all batteries are backwards compatible.

[daveb]

Time to pull the battery, put it on a good high amp charger for a few days and see what happens. If the charge rate amperage tapers down to an amp or two, let it sit for a day without a charge and if it holds a 12.6 or higher voltage (without any load applied), I'd take to a place that can do a load check. You can do a load check yourself and can search how to do it, but better to take it to a place that does that for a service...like maybe an RV shop or maybe a parts store that knows how to do them. It's typical for a failing AGM battery to hold a surface charge higher than 12.8 shortly after being charged, but often it will drop in voltage to below 12.6 or lower over time indicating the battery is toast. A good battery will hold a good voltage for a month...bad batteries won't.


Always monitor the charge and if the battery gets unusually warm, stop the charge.

https://carnesmechanical.com/how-to-...n-agm-battery/

[jlsm]

Originally Posted by daveb

Time to pull the battery, put it on a good high amp charger for a few days and see what happens. If the charge rate amperage tapers down to an amp or two, let it sit for a day without a charge and if it holds a 12.6 or higher voltage (without any load applied), I'd take to a place that can do a load check. You can do a load check yourself and can search how to do it, but better to take it to a place that does that for a service...like maybe an RV shop or maybe a parts store that knows how to do them. It's typical for a failing AGM battery to hold a surface charge higher than 12.8 shortly after being charged, but often it will drop in voltage to below 12.6 or lower over time indicating the battery is toast. A good battery will hold a good voltage for a month...bad batteries won't.


Always monitor the charge and if the battery gets unusually warm, stop the charge.

https://carnesmechanical.com/how-to-...n-agm-battery/

What would you consider a high amp? The charger I have has 2, 10 and 70 amp. I am thinking that while we drive and charge with alternator, the amps should be pretty high. Heading out this weekend for a 5 hr drive each direction. We will use hookups overnight, so it should be maxed out by the time we get back. Then I'll see if it holds.

Originally Posted by rt66paul

For what it is worth, you can buy a solar charge panel that charges(tops off) the battery through the cigarette lighter. If your isolator isn't working correctly, maybe this will charge the battery up enough to see?
These panels were sold with VWs in the 90s and 00s, I got one for less than $20 I use to keep my battery topped off. I see some at Amazon for $25, that charge through the cig lighter, or just buy something with a cig lighter lead and connect it to a battery charger, all batteries are backwards compatible.

Interesting - thanks! I wonder if I can plug it in to a house-side cigarette lighter.

[Scalf77]

A weekend of driving and being plugged in should complete a full charge. It would still be nice to know what charger/converter you have in the van. You also want to take this time with a possible bad battery and figure out your charging plans moving forward. That way if you do get a new battery you will make it last as long as possible. It can be very difficult to look at the voltage during a charge cycle and determine what state the battery is in.

In the following post on Battery Charging I went through three different charging methods, Shore Power, Solar, and Alternator. The important thing to notice is time, it takes time to charge the battery.

-greg

[jlsm]

Originally Posted by Scalf77

A weekend of driving and being plugged in should complete a full charge. It would still be nice to know what charger/converter you have in the van. You also want to take this time with a possible bad battery and figure out your charging plans moving forward. That way if you do get a new battery you will make it last as long as possible. It can be very difficult to look at the voltage during a charge cycle and determine what state the battery is in.

In the following post on Battery Charging I went through three different charging methods, Shore Power, Solar, and Alternator. The important thing to notice is time, it takes time to charge the battery.

-greg

I would love to know as well, but it's under the sofa seat inside a metal box that opens from the top . I'm not sure how to do that with the sofa. I love the battery post - I am a scientist (but not an engineer).

[jlsm]

Originally Posted by jlsm

I would love to know as well, but it's under the sofa seat inside a metal box that opens from the top . I'm not sure how to do that with the sofa. I love the battery post - I am a scientist (but not an engineer).

Originally Posted by Scalf77

A weekend of driving and being plugged in should complete a full charge. It would still be nice to know what charger/converter you have in the van. You also want to take this time with a possible bad battery and figure out your charging plans moving forward. That way if you do get a new battery you will make it last as long as possible. It can be very difficult to look at the voltage during a charge cycle and determine what state the battery is in.

In the following post on Battery Charging I went through three different charging methods, Shore Power, Solar, and Alternator. The important thing to notice is time, it takes time to charge the battery.

-greg

My best laid plans were cancelled due to a mandatory evacuation of our campsite, so I did not have the opportunity to see if I could fully charge the battery. I did look under the seat and inside a metal box and I can see the charger is a Magnetek. I can't see the model number. I believe the first owner swapped this for the Trace inverter before selling it the current owner, from whom I'm borrowing the van.

If I don't need to replace the battery, my long term plan is to use the very cheap and clever suggestion by another member, i.e. to put plug a small solar trickle charger into the house side cigarette lighter. I am 75% sure this is working, and it cost $21 for a 10W model. There is only one cigarette lighter, so I can't plug in the Innova while the solar is plugged in.

[jlsm]

Originally Posted by rt66paul

For what it is worth, you can buy a solar charge panel that charges(tops off) the battery through the cigarette lighter. If your isolator isn't working correctly, maybe this will charge the battery up enough to see?
These panels were sold with VWs in the 90s and 00s, I got one for less than $20 I use to keep my battery topped off. I see some at Amazon for $25, that charge through the cig lighter, or just buy something with a cig lighter lead and connect it to a battery charger, all batteries are backwards compatible.

I think this is working! I have it plugged into the house-side cigarette lighter and it seems to be keeping the battery from dropping in voltage. $21 well-spent. Thanks so much.

[Scalf77]

This becomes a math exercise.

-greg

[daveb]

The test will be when the van sits without any charge and where the battery voltage ends up when you put a load to it as you use it throughout the night hours.