# question

asked

## MPPT Operating Voltage Range - SmartSolar Charger MPPT 150/70-MC4

What is the MPPT input voltage range (minimum to maximum PV operating DC input voltage range over which the MPPT can effectively maximise the power output) for the SmartSolar Charger MPPT 150/70-MC4?

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
JohnC answered ยท

Hi Karl. In theory, any V greater than 5V more than the Vbat, all the way to 150V.

But panel performance differs from published spec sheets with weather, temp, etc., so this answer is a little 'mushy'.

In poor light (say daybreak) my own panels find a Vmp only about half nameplate, so it's nice to be 'up-there' somewhat.

Please ask if you have a specific application.

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

karl answered ยท

Hello John, thank you very much for taking the time to reply.

So just to confirm, the MPPT of the SmartSolar Charger MPPT 150/70-MC4 will actively optimise the maximum power output of the PV array over the full operating voltage window of the device; 5V greater than nominal battery system voltage (in this case 24 + 5 = 29V DC) right up to the maximum Voc rating of the device of 150 VDC?

When the voltage drops to 29 VDC and the MPPT wants to drop the voltage lower to optimise the array output will the solar charge controller simply continue to sit at 29 VDC?

Is there a similar upper voltage limit for the operation of the MPPT or can the device literally in theory raise the operating voltage of the MPPT right up to 150VDC to optimise the output of the PV array?

Thank you for your time and help with this

1 comment

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

ยท

Yeh I did say my answer was a little mushy. I was talking Voc generally, and Vmp is always lower. That 5V delta becomes 1V in production (now Vmp), so a 48V batt under charge might exceed 58V. Then maybe the Vmp range would have a lower limit of ~60V.

The upper 150V limit is Voc, so the equivalent Vmp might be say 130V.

In practice that range can be near fully utilized under varying light conditions, so it's nice to be able to optimally string your panels. My own (48V) system ranges from ~60V (sunup/sundown) to just over 120V mpp at full tilt. Works nicely for me by extracting every last Wh available, even in the worst conditions.

Hope this makes sense. You may also have spotted a Vmp range stated in domestic ac- coupled inverters. That doesn't apply to Victron mppt's, and you can utilize the full range, subject to the limits I've tried to explain.

0 Likes 0 ยท