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Semi truck setup Looking for a little info on DC-DC charger for 600ah lithium

I

IMSITTINGINYOURCHAIR

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Hello, First post here.

I have put together an E-APU for my semi truck to reduce idle time in the summer. I have three LiTime 200AH batteries in parallel, charging them is a LiTime 60a dc-dc unit, my truck has a 240a alternator installed and handles the load just fine. the batteries power a 12v PSW inverter that is running an ecoflow dual hose ac along with a mini fridge and small microwave. The system is installed under my sleeper bed. while charging I have a couple of small fans to direct air around and out from under there by propping the bed up and pushing the air out from the three inch gap. doing this I have kept a check on temperatures and noticed the charger was able to keep cool air around it. Wire sizes, 1/0 from batteries to input of charger, something like 10 ft, not sure on length, 150a breaker at truck battery, 6ga from charger to battery, 1/0 from batteries to inverter aslo 1/0 jumpers for the parellel connetion.

This week I had to have the charger replaced after about two or three weeks because something inside got hot on the charger and charging stopped working. I Looked inside the failed one as best as I could and comparing to the new one it looks like the traces below the relay are what burned up. I am wondering if the charger can handle charging for the near ten hours it takes after running the ac overnight. If this new one fails the same way I am considering attempting a repair by beefing up the trace they have a layer of solder on and just eating the cost of replacement if that is a failure.

Any input is welcome.
 
IMSITTINGINYOURCHAIR said:
Hello, First post here.

I have put together an E-APU for my semi truck to reduce idle time in the summer. I have three LiTime 200AH batteries in parallel, charging them is a LiTime 60a dc-dc unit, my truck has a 240a alternator installed and handles the load just fine. the batteries power a 12v PSW inverter that is running an ecoflow dual hose ac along with a mini fridge and small microwave. The system is installed under my sleeper bed. while charging I have a couple of small fans to direct air around and out from under there by propping the bed up and pushing the air out from the three inch gap. doing this I have kept a check on temperatures and noticed the charger was able to keep cool air around it. Wire sizes, 1/0 from batteries to input of charger, something like 10 ft, not sure on length, 150a breaker at truck battery, 6ga from charger to battery, 1/0 from batteries to inverter aslo 1/0 jumpers for the parellel connetion.

This week I had to have the charger replaced after about two or three weeks because something inside got hot on the charger and charging stopped working. I Looked inside the failed one as best as I could and comparing to the new one it looks like the traces below the relay are what burned up. I am wondering if the charger can handle charging for the near ten hours it takes after running the ac overnight. If this new one fails the same way I am considering attempting a repair by beefing up the trace they have a layer of solder on and just eating the cost of replacement if that is a failure.

Any input is welcome.
Click to expand...
I am running almost exactly the same system, my 50 amp Redarc dc/dc charger will get hot enough to reduce charging amperage. I am installing larger ventilation fans and a parking cooler.

50D02D22-B29D-49CC-9645-232365DE33F1.png


I am charging two 280ah diy batteries that power a 12/3000 victron inverter, rv frig, microwave, I will be adding another dc/dc charger for 100 amps so adding more heat. I have been using the Redarc for over two years with no issues other than de-rating from heat.

D66C65D0-E25D-4331-9844-CDFB8B85D7B9.jpeg63126FE2-B6B2-4721-A371-ECEA1AB70266.jpegC7095644-E2A7-496E-9EE0-3DEC1953ECDC.jpegE54388B2-A01F-41BA-A817-3A1F37E59A1A.jpeg
 
I bought the litime 60a DC-DC charger. I havent hooked it up yet and im probably going to go with a victron XS 50a instead. Mine is on a schoolbus outside the temperature controlled zone. I have doubts about the litime handling the heat.
 
I didn’t want to add more heat to the cab from the inverter when running a/c or refrigerator so I am going with a 12 volt split a/c and 12volt compressor frig.
 
IMSITTINGINYOURCHAIR said:
Wire sizes, 1/0 from batteries to input of charger, something like 10 ft, not sure on length, 150a breaker at truck battery, 6ga from charger to battery, 1/0 from batteries to inverter aslo 1/0 jumpers for the parellel connetion.
Click to expand...

Wire size from the alternator to the charger looks good. Why did you step down to 6 awg for charger to battery? If the distance from the charger to the battery is under 6' (12' round trip) then 6 awg is OK. The voltage drop with a 6' distance (one way) is 2.44%, which is below the 3% voltage drop we try to not exceed.

With the new charger installed, keep an eye on component temperatures. Charger, connections, wire. If you can feel a hot spot with your fingers that is hotter than any other location you're checking, that's what you need to focus on. Bad connections can cause voltage drop which can cause issues in other areas.

@IMSITTINGINYOURCHAIR , Welcome to forum!
 
HRTKD said:
Wire size from the alternator to the charger looks good. Why did you step down to 6 awg for charger to battery? If the distance from the charger to the battery is under 6' (12' round trip) then 6 awg is OK. The voltage drop with a 6' distance (one way) is 2.44%, which is below the 3% voltage drop we try to not exceed.

With the new charger installed, keep an eye on component temperatures. Charger, connections, wire. If you can feel a hot spot with your fingers that is hotter than any other location you're checking, that's what you need to focus on. Bad connections can cause voltage drop which can cause issues in other areas.

@IMSITTINGINYOURCHAIR , Welcome to forum!
Click to expand...
Yeah, the 6ga wire is maybe a foot long, it connects at the inverter then goes to the batteries over the 1/0 wire from there. No noticeable warm spots. Something funny I noticed, from their supplied manual it suggests for 3' to 16' to run 6ga in and 4ga out. I will double check voltage drop tomorrow when I install the replacement charger, I have about 4ft of 1/0 left, if I see anything I'll just make up a couple more cables.
 
S Davis said:
I am installing larger ventilation fans and a parking cooler.
Click to expand...
The parking ac is my next move, likely getting it for next summer, I haven't been blown away with the ecoflow wave2 but it does a good job for overnight. the problem lies with it's programming. If i set it at 68, it will cool to 5f below that, and the fan remains on even when it satisfies the requested temperature, so now it's too cold and then it gets humid from blowing across a wet coil. If it's just right outside it will maintain around setpoint but it's gotta be around 80 to 90 overnight before it will do that.
 
IMSITTINGINYOURCHAIR said:
Yeah, the 6ga wire is maybe a foot long, it connects at the inverter then goes to the batteries over the 1/0 wire from there. No noticeable warm spots. Something funny I noticed, from their supplied manual it suggests for 3' to 16' to run 6ga in and 4ga out. I will double check voltage drop tomorrow when I install the replacement charger, I have about 4ft of 1/0 left, if I see anything I'll just make up a couple more cables.
Click to expand...

Good luck, I hope the replacement charger works.
 
New charger doing its job so far, volt drop from end of battery back to the charger was 0.03v across each lead. I did a little looking around yesterday and if this one fails again I am looking at the victron 50a model.
 
Also, now that I look into it I'll probably just go ahead and get one ordered. From what I am reading I'll get back quite a few amps that the li time is just dumping as waste heat, with the 50 vs 60 I might have to idle a bit more on the hotter evenings when I dont quite run enough to fully charge the bank.
 
IMSITTINGINYOURCHAIR said:
Also, now that I look into it I'll probably just go ahead and get one ordered. From what I am reading I'll get back quite a few amps that the li time is just dumping as waste heat, with the 50 vs 60 I might have to idle a bit more on the hotter evenings when I dont quite run enough to fully charge the bank.
Click to expand...

I think I've read on the forum that the Orion XS runs surprisingly cooler than other Victron chargers.
 
Perhaps just wire it this way instead of stepping down the wire size.

Just add another battery pack the same way as shown for more of them.

This also allows isolating off a battery that has a BMS tripped to re-set it.

Sterling makes some battery to battery chargers as well as SEC America
 

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