Upgrading AGM to Lithium in RV and retaining slide and awning safety features.

Trying to determine items need to replace old small AGM battery bank with lithium in my RV. 2014 Forest River Sunseeker on an e 450 chassis.

Can't find any information about maintaining safety controls for slides and awning in the current set up tied to the Trombetta relay when upgrading. I know I need to install DC to DC charger, but also maintain those safety features. any help would be appreciated. I was thinking I would just put the DC to DC charger in front of the current relay and wiring with a DC to DC with MPPT , but when I add solar that won't work as when parked and no ignition 12 volt I don't think the Trombetta relay will pass the solar to the battery bank.

There is also a battery isolation manager from Precision Product in there and I think that is what controls the safety features for the slides and awning. Any help would be appreciated.

John

Precision products makes a unit for lead/Li integration for the RV. If concerned about your slide/awning power simply move the connections over to the AGM side of the system.

On our 2016 Axis the slide and awning are interlocked with the E450 ignition system. If ignition is on can't open the slide or awning. Relays are located below drivers seat reached through outside storage. The Trombetta is only used when engine is running to charge house batteries. I removed it as the contacts were always failing. Replaced with a manual switch.
The interlock safeties should not care what type of house batteries you have.

scrubjaysnest said:

On our 2016 Axis the slide and awning are interlocked with the E450 ignition system. If ignition is on can't open the slide or awning. Relays are located below drivers seat reached through outside storage. The Trombetta is only used when engine is running to charge house batteries. I removed it as the contacts were always failing. Replaced with a manual switch.
The interlock safeties should not care what type of house batteries you have.

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Yes it appears these may be tied to the 12 volt ignition lead on the Trombetta? in the step entry well to the RV. I am guessing these might be tied to a normally closed switch/relay that once it senses ignition voltage it opens the relay and won't allow the slide or awning to operate. I just don't have any wiring diagrams for this whole set up - not sure how the Battery Isolation Manager plays into this and the Trombetta relay and these other lockouts. I know the safeties are not reliant on the type of battery I am just trying to figure out where to put my DC to DC charger (especially if I want to add MPPT for future solar). If I had no plans for future solar I would just put the DC to DC charger in front of everything I currently have and when I fire up the coach the DC to DC charger will just limit the current draw from the alternator/battery into the current relay and safety setup. But if I inject solar with a DC to DC and MPPT device in front of that current set up unless the engine is running the solar will never make it past the current Trombetta relay to the batteries. I could use a standalone MPPT controller and inject it after the relay, but I was hoping to kill two birds with one device and not two separate devices.

Now as I am a newbie I could be 100% wrong about all of this.........

grizzzman said:

Precision products makes a unit for lead/Li integration for the RV. If concerned about your slide/awning power simply move the connections over to the AGM side of the system.

https://invertersrus.com/wp-content/uploads/2020/03/Li-BIM225-Datasheet.pdf

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Yes I have looked at this LI Bim 225 the concern I have is I only have a 120 amp alternator and this device just cycle on for 15 minutes, off to 20 minutes to help prevent over heating of the alternator. During the 15 minutes of on time if my lithium batteries are fairly depleted it has 15 minutes to suck all the current from the alternator and probably more that 120 amps, so what damage could/would happen to the alternator during that run time. A DC to DC charger throttles/limits the max current draw to say 20 or 40 amps, never allowing the alternator to exceed current rating and burn it up.

I don't follow your comment about moving the slide/awning over to the AGM side....do you mean the chassis side? They may be there already as I have no wiring diagrams as to how this whole thing is wired together.

Now as I am a newbie I could be 100% wrong about all of this.........

jvidosh said:

Yes I have looked at this LI Bim 225 the concern I have is I only have a 120 amp alternator and this device just cycle on for 15 minutes, off to 20 minutes to help prevent over heating of the alternator. During the 15 minutes of on time if my lithium batteries are fairly depleted it has 15 minutes to suck all the current from the alternator and probably more that 120 amps, so what damage could/would happen to the alternator during that run time. A DC to DC charger throttles/limits the max current draw to say 20 or 40 amps, never allowing the alternator to exceed current rating and burn it up.

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Well then install a DC to DC charger on the coach side of the Li Bim. As a example the Renogy 40 amp DC to DC charger that will limit charging to 20 amps with the flick of a switch.

jvidosh said:

I don't follow your comment about moving the slide/awning over to the AGM side....do you mean the chassis side?

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Yes

jvidosh said:

They may be there already as I have no wiring diagrams as to how this whole thing is wired together.

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I would disconnect the coach batteries then see if the awning/slides work to test what side likely powers them.

jvidosh said:

Now as I am a newbie I could be 100% wrong about all of this.........

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Some wiring diagrams are on the Thor forums. Also I had some emailed to me by tech support.