I have a Quattro 24/5000/120 supporting 3 24V/230Ah batteries in parallel. Each batteries recommended charge current is 50A. This means that I need a charge current of 150A from the Quattro correct? I do realize that the unit’s max charge current setting is 120A. Should I set it to 120A? My batteries are connected to my battery cutoff switch via 5-ft (one way) 1/0 cable fused with a 250A fuse.
50 amps seems low for a 230 Ah battery at first blush, but it’s a 24 volt battery so it’s not bad. I try to not exceed .5C which in your case would be 115 amps.
If you need to get them charged as fast as possible to reduce the cost of the charging source (a generator for example) then setting the Quattro to its highest charge rate of 120 amps makes sense. The cable lengths come into play when calculating if the 1/0 cable is sufficient. A 20’ round trip (10’ each way) with 1/0 cable at 120 amps at 24 volts will result in a 1% voltage drop, which is well under the 3% maximum.
If you have other charge sources, you’ll need to take them into account to avoid exceeding the 50 amp recommended charge rate.
Thanks. I updated my post to the length of my 1/0 cable to be 5-ft one way, so 10-ft round trip. I’ve set my Quattro charge current to 120A, giving each battery (3 in parallel) 40A charge current. My only other charging source is the AC2 input of my Quattro, which uses my van’s alternator via Renogy 3000 12Vdc→120Vac inverter, which means, the 2 AC inputs are never used at the same time.
The nice thing about the Quattro is that you have two distinct AC inputs and you can limit the incoming amps on each of them independently. My AC 2 is the on-board generator, which I have limited to 27 amps (due to elevation). The AC 1 is shore power so it’s the full 30 amps.
What are you limiting the incoming amps to when the alternator is the source? I can probably guess why you’re using an inverter there, so I won’t comment about using a DC-DC instead.
The Renogy 3000 is rated at 25A continuous current output on its 120Vac output side, so I limit the Quattro AC2-in to 20A. In hindsight, I probably could’ve used the Multiplus-II + a Orion XS DC-DC charger. I also have a Victron MPPT 100/30 for 24V/500W solar charging.
This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.