EB150 not charging unless I unplug and replug the DC solar cable

Summary: Unless I unplug and plug in my solar input DC7909 cable into my EB150 in the morning after the sun has risen, the unit will not charge for the whole day. An in-line Watt mater shows ~41V open circuit when this is happening. Additionally, the EB150 won’t turn on when I long-press the power button until I remove the DC input cable and re-insert it.

Video of the issue (filmed just after sunrise at 8:45am): Bluetti EB150 Solar Input Problem - YouTube

Analysis:

  • The polarity is correct, else the unit wouldn’t charge after I merely re-insert the DC cable
  • I’m using the provided MC4 to DC7909 that came with my EB150
  • I’ve used my EB150 for 3 weeks and have had this happen almost every single day
  • My solar panel setup is as follows: 2 Renogy 100W suitcases in series on one string and 2 Golabs 100W SF100 panels in series on another string. Both strings are then combined in parallel into my EB150. The open circuit voltage difference between the two strings is 3-4V as measured. I know this isn’t ideal, but ultimately I still generate more electricity than if I didn’t do this.
  • At 8:45am when I filmed this I don’t expect many input watts, plus there were some clouds in the sky which is why after re-inserting the DC plug there wasn’t much energy going in.

I’m going to write to Bluetti support but wanted to get your opinions as well.

Quick update: With just the one string of 2x 100W Renogy 12V suitcases wired in series my EB150 still showed the same behavior of refusing to charge in the morning with the DC input cable left plugged in as the sun rose. Tomorrow I will try the same but with just the other 2x 100W Golabs SF100 panels in series wired into the EB150.

My working hypothesis is that the EB150’s MPPT controller enters a stopped/failed state during sun rise due to the low voltage and amps being input into the DC port and is unable to self reset/recover.

Any EB120/150/180/240 owners out there with the same issue?

I have an EB150. I have not seen that issue. I have limited sun exposure in the area that I live. It is mostly indirect, In the afternoons it is foggy almost everyday. It it is very foggy, I see no input on the front panel of the EB150. I measure the current with my clamp on ammeter and it does show a small amount of current (I think 0.75 or less). So, there is a light charge or maybe that is a quiescent current that is just enough to keep the MPPT in standby state. I noticed that the display does not come on until it reaches 15W. That seems to be the minimum. Even if it is slightly foggy with indirect sunlight, I usually will see a small amount of charge (15 to 25W). Maybe someone else can chime in on the issue with your Power on switch.