Why Interstate Lifeline AGM batteries die

[Boxster1971]

Originally Posted by Mcrider

Mike, I looked at the BIM wiring diagram and it would be easy to wire a relay into the ignition input on the BIM and use a NC relay on the solar input. Then no switches required. Ignition on solar off.

Cleaver - that should work nicely.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[Boxster1971]

Originally Posted by Mcrider

According to AS wiring is fit for 300 Watts. It is 10AWG according to the drawings so just fine for 20+ amps with an acceptable voltage drop.

... and if I recall correctly the stock wire run from the solar controller to the thermal CB is very short.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[amirm]

Originally Posted by Boxster1971

How do you know your batteries are getting fully charged when you drive?

I don't right now . I was wishing for a proper battery monitoring gauge.

By the way you can also tell when the batteries are connected by checking the voltage on the tank monitor panel.

On mine, it frequently shows a different voltage than Magnum or the Solar controller. Sometime they are the same. Other times they are not. Have to figure out where the sense voltage is for all of this and source of discrepancy.

[Boxster1971]

Originally Posted by amirm

...... On mine, it frequently shows a different voltage than Magnum or the Solar controller. Sometime they are the same. Other times they are not. Have to figure out where the sense voltage is for all of this and source of discrepancy.

Unless a voltmeter is calibrated they can vary a lot. The Magnum is probably the most accurate. The Atkinson solar controller display voltage is the worst. The tank monitor voltages are just a way to do a quick check on the voltages is the two battery systems. If they are the same the BIM has closed isolation relay and the two battery systems are tied together.

[LB_3]

I don't understand the need to disconnect the solar charger when the vehicle is running. My solar charger will see the elevated voltage from the alternator and either assume the battery is already full or that it is applying too much current. Either way, the charge controller will decrease its output our turn off altogether.

[lewster]

The stock Atkinson solar controller is not that 'smart'.


Lew Farber
RVIA/RVDA Nationally Certified Master Tech
ABYC Certified Master Marine Electrician
Master Tech Energy Systems, Inc.
AM Solar Certified Installation Center*AMS Lithium Batteries
Lifeline AGM Batteries**Magnum Inverters***Victron Energy Components
541-490-6357

[amirm]

Originally Posted by LB_3

I don't understand the need to disconnect the solar charger when the vehicle is running. My solar charger will see the elevated voltage from the alternator and either assume the battery is already full or that it is applying too much current. Either way, the charge controller will decrease its output our turn off altogether.

That is what I observed today too. As soon as I started the engine,the Solar current draw went from 3.2 amps to just 0.2.

[Boxster1971]

Originally Posted by LB_3

I don't understand the need to disconnect the solar charger when the vehicle is running. My solar charger will see the elevated voltage from the alternator and either assume the battery is already full or that it is applying too much current. Either way, the charge controller will decrease its output our turn off altogether.

I would not recommend disconnecting the solar. My analysis was aimed at a specific Interstate configuration common from 2013-2015. My observations were based on what I see on my 2013 model. The problem I was having centered on the issue of not getting an alternator charge when needed, like batteries down 20-30%. On a typical day the 50-100 watt solar will not recover that much of an energy loss.

The logic in the later model BIM's may have been upgraded to handle this situation better. I noticed that the more recent data sheets on the PCI BIM no longer give specific voltages like my older model. Now they just say relay turns on when coach battery voltage is "low" with engine running.

As Lew pointed out the stock Atkinson solar controller is just not that smart.


- - Mike
2013 Lounge EXT on 2012 Sprinter

[Mcrid]

I did a little research and it appears the Atkinson will drop to ~.25 amps when charged and then display "chr" on the remote display. I've seen this pop up when the engine is running so I'm suspecting the BIM does connect and charge despite the solar voltage. I may have to test this out.

[UKDUDE]

Originally Posted by Mcrider

I did a little research and it appears the Atkinson will drop to ~.25 amps when charged and then display "chr" on the remote display. I've seen this pop up when the engine is running so I'm suspecting the BIM does connect and charge despite the solar voltage. I may have to test this out.

I spoke to someone at Atkinson about this several months ago: "chr" is displayed when the amp input is equal or less than 0.2A. A display of "0" indicates the controller has shut off.


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