Li batteries to Inverter to LTS?

[geoff123]

Hello all,
First off - I really appreciate all the amazing details found in this forum on the minutia of these amazing rigs. We are rolling a 1998 Chinook Premier with a smile. The information has been super helpful and definitely boosted my confidence to tackle some of the systems upgrades of the Chinook especially in the electrical department. I have recently done a total revamp of the dc side of things including new lithium batteries (2 -90 amp hour - moved under the sofa), a new Redarc BCDC1240 controller, 2 new 100w solar panels, a Redarc SBI12 isolater unit to gate power from the coach batteries back to the start battery if needed, and a marine style manual off/on switch for the batteries to busbars to connect a 1500w inverter and leads to the ac/dc distribution panel. I had previously upgraded my converter to the PD4645V following Clay's concise instructions, with the switch to Li unfortunately the charge voltage profile is not high enough for Li, so the converter is turned off at the breaker. The ATS works when plugged into shore power or generator for the microwave and I have removed the AC unit for a skylight like Blue did. What is the best approach to add the battery powered Inverter to the ATS system? or is the best option to scrap it and go with a marine style 3 way - and if so any concerns with ac distribution panel as it is? Overall, I am super pleased with the new Redarc controller and solar panels - It keeps the batteries charged up, and even supports driving with the 3 way fridge on DC with charge to spare. I can run the microwave off of the inverter with a heavy extension cord but it would be nice to load microwave outlet and the other AC outlets with the inverter wired in to the ATS somehow. I also ran 2 AWG wires direct under the sofa from the bus bars to the distribution panels and nixed using the smaller 8awg wires that ran up the pillar and over the window frame. So I think I am good for higher amp delivery to the ac panel.
Cheers!

[geoff123]

correction - I will be wiring back from the inverter to the AC with AC power so disregard the last sentence about the 2 AWG wires The inverter is a very short run off the bus bars with a fuse block(200amp) and 1/0 wire.

[chin_k]

I am trying to see if I can use the Hubbel HBL1388 to manually switch the inverter into the outlets, and cut off the converter power. It is rated for 30 Amp, and 240V AC, and I originally plan to use it for something else. The idea is to have the output from the ATS and the inverter go to the manual Hubbel switch on the two separate inputs, and let me switch between them. If I do not need to switch the neutral, then I can use the second pole to cut off the power to the converter/charger with the same switch. You may want to use one that does not have a center off like mine. For the original application, I need the center off. I think I got mine for around $30.

You may also get an additional ATS and have it switched automatically, without having to cut a hole to mount the manual switch.

For Lithium, call Progress Dynamics and see if they sell a lithium charging module. The chance maybe small, but it will not hurt to ask.

It is so much easier to run the AC wiring compare to low voltage, so it is good that you keep the inverter close to the batteries. Definitely save you tons of money on copper there.

[Warthogg]

I would open the box on the top of the ATS and see if during transfer the neutral opens. If it does open then use your switch appropriately. If it doesn't open then Bond all the neutrals together and use the other side of the switch to control your converter. If you aren't able to use the switch to control the converter you can always move the converter to its own breaker and open that breaker when you use your inverter. Kudos for recognizing that you don't want to charge your batteries with your batteries.

Battleborn also offers all kinds of different products and devices for LiFepo4 systems.

[chin_k]

I think most ATS switches both neutral and hot, but I forget what the ATS one do in ours rig. I do not have any reason to get to the brown box until I am ready to do the update.... chicken or egg dilemma here.

Edit: I looked at various ATS, and they all have multiple poles, so I am sure the Surepower ATS that we have switches the neutral. I guess the safest thing for me to do is either cut off the charger on the breaker panel, or have a 12V powered remote switch that shut it off when the inverter is pulling 12 V DC from the battery.

[geoff123]

Thanks Chin and Warthogg for the replies - my primary goal is to use the inverter as a 3rd source for the ATS, or manually perhaps, to load the ac plugs and microwave without having shore power or the generator on. The highest priority in the ATS to generator, second priority to shore power, and default priority to inverter. The batteries are almost always kept full charge - as far as I know with a 10 day trip under the belt with good sunny weather - they charge from solar and driving with the BCDC charger - it delivers close to 40 amps if needed with priority to charge coming from solar, so at this point not as worried about using the converter to charge the batteries - for converters I have looked at the 9000 series from Power Dynamics, but like the idea of a module swap - good suggestion, I will ask them. We mostly boondock, but it is nice to plug into shore power and directly power the fridge with AC if we do make a stop at a campsite with hookups and have the backup of the generator if we do drain the batteries low. I think the converter, as is, will charge the Li batteries to 60% - 65% according to the LionEnergy Battery documentation -that I received with the voltage set where it is.

[chin_k]

Looks like it should work for you, but you need to make sure the battery capacity is enough for you to run the appliance. I assume your inverter can handle the burst in load when the microwave turns on, etc. You go with a second ATS or a manual switch, such as the Hubbel or some of the marine manual transfer switch (looks cooler!). You want to be able to cut off the inverter when the voltage get too low, and I think there are some products out there that can do that. You don't want to drain down your Li too much since they will get ruin if you let the converter run. Some smart converter (maybe that is the type that you have) will auto shut off when the voltage is too low, but you need to make sure the voltage cutoff match with your Li application. I would hardwired the inverter to the AC with the ATS/switch, definitely better than using an extension cord.

[geoff123]

Thanks for the input, I did check the microwave peak load with an inline meter and the inverter has enough ceiling. Running the microwave pulls between 100 - 110 amps according to the shunt meter, which is a lot but I within the limits of the system and only for a few minutes most of the time. I will look into a second ATS vs switch - I am leaning to the simpler solution with a 3 way switch so I can't screw it up and will be conscious of where the power is coming from.