Just to log a solution into the forum.... I asked the other day about combining the CHG and DISCHG outputs from the Chargery BMS to ONE relay. The manual offered a solution of using some opto isolated relay board that actually ends up driving two electromechanical relays... not optimal.
I ordered some $3 optoisolated DC relays from ebay.
https://www.ebay.com/itm/322209858572 3-32V DC 1-Channel SSR Solid State Relay High-low Trigger 5A 5v 12v For Arduino . The input of this relay module requires 12v and a ground and a 12v switched input. So I connected the chargery black wire to the DC- and either one of their red wires to the DC+ input. The remaining Chargery red wire goes to the CH1 input on that relay module. If chargery drops either of the CHG or DISCHG 12v's, the relay module will not operate. So this is a very simple $3 low current draw solution to combine the two outputs from the chargery.
Depending on how I end up feeling about the chargery BMS, I may end up using the above isolator and the gigavax GV241FAX for my contactor.
As it is, I have a battery pack just sitting doing nothing but running the chargery BMS and it has run mybattery down to 53v from 55.8 two weeks ago... no problem.... but.... since the shunt isn't calibrated right, it shows 1a charge even though it should say "storage" mode. Because of this the SOC counter is NOT registering the voltage loss as a lower SOC. It still shows 14340wh available.
I really hate to have to say this... but I gotta give up on the chargery DCC. I LOVE LOVE LOVE the idea of a bidirectional switch. But the soft start only works when you manually turn the DCC on. If the BMS commands it off there is no soft start when the BMS commands it on again. This caused me to blow up my first DCC. So I ordered another one and two more BMS's and two more DCC's. I replaced the shorted out DCC with new and the isolation board lights started to flash. I replaced a 3rd DCC and it also flashes LEDs. It may be the ISO board that is killing these things. I put one of the flashing DCCs on my bench last night and put 12v on one of the control inputs and the power light came on as expected. I put 12v on the second contorl input and the status LED came on as expected... what wasn't expected was the little puff of smoke that came from one of the surface mount resistors in the rear of the unit.
So I have 4 DCC units... 1)shuts off charging but will not shut off discharging, 2)lights flash when connected to ISO board and little puff ofsmoke, 3)lights flash when connected to ISO board, 4)new in box, afraid to take it out.
As I said, I love the /idea/ of these, but if I can't get these things going at this time, how can I depend on them to protect my batteries when I'm not looking?
To this end I have ordered a QUCC BMS from aliexpress. It has that gigavac look alike contactor on it. I have heard of some issues with that contactor, so I expect that one day I'll have to replace that contactor with the real gigavac GV241FAX or GV241CAX.
Not to be all negative... Jason at Chargery has been emailing me with suggestions for the DCC problems. His emails are ALWAYS prompt and are VERY helpful. Absolutely wonderful support. We're at the point where I gotta mail 3 DCC units to him so they can be repaired and I'm not sure it's worth the postage because I'll just end up with more DCCs that I'll just have to tip toe around.
