Question about discharging with second battery connected

I have my AC200 Max connected with a B230 battery, battery and unit are both on, Trying to do a run test with my deep freeze and it seems that only the main unit battery is discharging. Is this the way its supposed to work? I would think starting from 100% charge both battery’s would share the load equally and discharge together. And if this is the case will the other battery take over when the first is depleted?

Hi, in my experience, using two B230 batteries, the SC200Max starts out discharging the internal battery. Once it goes below a certain point, I see about 10-15% difference between internal and B230, then it starts using the B230’s. As it gets close to 0% it equals out. So it seem to me the internal unit is always leading the discharge 10-15%, but it is also the last to reach 100% during charging. Regardless, you will utilize the full system capacity if you do a full discharge.

I assume you see the B230 SOC % on the BMS screen and the B230 green light is on?

Thanks for your reply. A slight differential would be acceptable but I’m currently at 65% on the main and still 100% on the B230. When I go to the battery information page the B230 always says “standby” whereas the main unit says “discharge”. But at least the battery is recognized as being there so I guess I will just wait it out and see what happens. My AC load is intermittent and small (small chest freezer). And yes the unit is on as well. Thanks again for your reply.

You are welcome, one more note, if the load is very light, say 100W or so, then it does take more from the main unit before engaging the B230. You should try with a hair dryer or some heavier load. Then typically the second battery is engaged immediately.

Thanks, I suspected I needed a heavier load. But I waited it out and what you said is true, The second battery finally came out of standby and picked up the load. I suspected that maybe there was a voltage differential and one wouldn’t pick up until they were more closely matched. Next time I have them both at 100% I will check that out but for now I am pleased.

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