Keeping chassis battery charged using Amp-L-Start starting battery charger

[GoldenEra]

I have a 2017 Winnebago Era. The chassis battery is being drained by something if it sits for a few months.

I was considering a solar trickle charger until I came across the Amp-L-Start battery maintainer from LSL Products AMP-L-START Starting Battery Charger/Maintainer - Overview Page.

Does anyone have experience with this product? I am concerned about unintended consequences such as bypassing disconnects, etc. It is a Mercedes and they always do things that trick the DIY'r!

From the manufacture "Connected between your house and engine starting batteries, AMP-L-START "steals" some of the charging current from your house battery charger (or solar panels) to also keep your engine starting batteries charged.

I did see an old post https://www.classbforum.com/forums/f...tart-6405.html about the Trik-L-Start for another class-b that has given me some clues.

Thanks!
Cory

[avanti]

Originally Posted by ckill

I have a 2017 Winnebago Era. The chassis battery is being drained by something if it sits for a few months.

I was considering a solar trickle charger until I came across the Amp-L-Start battery maintainer from LSL Products AMP-L-START Starting Battery Charger/Maintainer - Overview Page.

Does anyone have experience with this product? I am concerned about unintended consequences such as bypassing disconnects, etc. It is a Mercedes and they always do things that trick the DIY'r!

From the manufacture "Connected between your house and engine starting batteries, AMP-L-START "steals" some of the charging current from your house battery charger (or solar panels) to also keep your engine starting batteries charged.

I did see an old post https://www.classbforum.com/forums/f...tart-6405.html about the Trik-L-Start for another class-b that has given me some

Many of us have Trik-L-Starts with very favorable results. Definitely recommended. I don't see any reason why you would want to pay the extra money for the larger Amp-L-Start.

Any modern vehicle will run down the battery after a few months (due to all the modern electronics that is never really "off") if it is left connected. That is why Sprinters provide the quick disconnect feature down by the accelerator pedal. If you disconnect the battery ground, it will stay charged for many months without issue. You are correct that you should never use that disconnect without also disconnecting the Trik-L-Start. It creates a sneak circuit. You can easily add a little switch to disable the Trik-L-Start if you are going to want to do this.

[hbn7hj]

Originally Posted by avanti

Many of us have Trik-L-Starts with very favorable results. Definitely recommended. I don't see any reason why you would want to pay the extra money for the larger Amp-L-Start.

As I understand it Amp-L-Start is smarter. It can deal with lithium batteries and it won’t cook your starter battery if you equalize your coach battery at 15.5 volts.

It also can charge at 15 amps but that probably is not important.

Trik-L-Start charges the starter battery when the coach battery reaches 13.2 volts. A lithium battery resting voltage is 13.3 volts and therein lies the problem. It never turns off.

I have the Trik-L-Start hooked to a lead acid battery but I would get the Amp-L-Start. It wasn’t available when I was buying.

[rowiebowie]

Welcome to the forum ckill (or should I say "GoldenEra")!

My '2012 Airstream Avenue came with the factory 20W (not a misprint) solar option. It was never enough to keep the two lead-acid coach batteries in float.

After I did my lithium battery/inverter-charger/DC to DC upgrade, there was no residual parasitic drain (zero, confirmed by my Battery Monitor). Since the lithium's inherently have negligible internal drain and the 20W solar is of no practical charging benefit to them, I switched my Victron controller to solely charge the chassis battery. Which it does nicely with float obtained daily within a couple of hours after sunrise.

The above suggests it doesn't take much solar to trickle-charge a coach battery.

[avanti]

Originally Posted by hbn7hj

As I understand it Amp-L-Start is smarter. It can deal with lithium batteries and it won’t cook your starter battery if you equalize your coach battery at 15.5 volts.

It also can charge at 15 amps but that probably is not important.

Trik-L-Start charges the starter battery when the coach battery reaches 13.2 volts. A lithium battery resting voltage is 13.3 volts and therein lies the problem. It never turns off.

Ah. According to this:
AMP-L-START Starting Battery Charger/Maintainer - Overview Page
these Lithium-friendly features are new with "Revision G2" of the Amp-L-Start. I wasn't aware. Thanks for the heads-up.

[mkguitar]

I use a Deltran Battery Tender- I have a number of these on my motorcycles etc



When parked at the house for long periods of time I connect to the vehicle battery


It is autosensing, even so I have it on a timer so that it only goes on for about an hour each night


an inexpensive solution, about $35


but I already had one




Mike

[hbn7hj]

Originally Posted by mkguitar

an inexpensive solution

Yep, but you can’t beat solar and Trik-L-Start.

[markopolo]

As with Avanti's Great West Van (a Sprinter like the the OP's RV), I think Winnebago also uses a low cost Solenoid to charge the coach batteries when the van engine is running. Adding a Trik-L-Start is an easy solution to keep the chassis battery in a ready to use state provided there's a charging source available such as solar or grid power.

There's is a small voltage drop (200mV IIRC) through the Trik-L-Start so there are technically better solutions such as using a single device such as a Blue Sea ACR with no voltage drop but typically there's added complexity to install.

For many folks adding a Trik-L-Start is an easy DIY solution. Seems ideal for the OP if he has solar or plugs in power when the van is stored.

[CJBill]

I use Battery Tender Jr. When plugged in to shore power I just have it plugged into one AC plug in the van and connect the other end to the auxillary 12v plug on the dash. The only disadvantage to the Trik-L-Start is you have to plug it in to the dash when you are going to be sitting for awhile. I have always been a little uncomfortable with the battery isolater as it has bare poles always hot to 12 volts and some mechanics will not be familiar with that. besides the hook up is simple.

Bill Dillinger
190 Popular 05/06

[avanti]

Originally Posted by CJBill

The only disadvantage to the Trik-L-Start is you have to plug it in to the dash when you are going to be sitting for awhile.

The big advantage of the Trik-L-Start products is that you install them and forget them. Can be done with or without an isolation relay.

[markopolo]

Originally Posted by CJBill

................. I have always been a little uncomfortable with the battery isolater as it has bare poles always hot to 12 volts and some mechanics will not be familiar with that. besides the hook up is simple.

Bill Dillinger
190 Popular 05/06

I have rubber terminal covers on mine.

[Buford Wilson]

I use the Xantrex Echo Charge which I think works in the same way as the Amp-L-Start.

I have Roadtrek Zion and the Echo Charge is perfect. I have to store the van outside with no 110 power for long periods. The solar panel keeps the house battery charged, which in turn keeps the starter battery charged.

I can monitor voltage through Drone Mobile. If the solar panel gets covered with snow, I can start the van remotely from anywhere. Charge the batteries that way.

[black88mx6]

I have successfully uses Trik-L-Start before on my 2016 ERA and it worked great.

Our new coach based on 2019 Sprinter will use the Xantrex Echo Charger. The extra AMP’s will allow us to not only charge the coach battery but also to keep the coach radio with wifi/lte cellular on for extended periods of time while it continues to work of the coach’s lithium batteries.

Mid City Engineering has a couple of hacks/fixes that can augment this usage. One that keeps the entertainment / head using running past the default timeout. They also have a high idle option that should allow recharge of the lithium batteries with all the restrictions already known about doing this with the Sprinter chassis.