question

bibbjs avatar image
bibbjs asked

MPPT low current output

I have two 100W panels wired in parallel to an MPPT 75/15 controller. I have gone through the whole basic list of why my output is low and done what I can to ensure a clean set up. I have full sun on both panels. I have a battery voltage level of between 12.0 and 12.7V and can load it up to keep the voltage fairly steady. I am in Bulk charge mode. I am seeing no more than 1.1A being delivered into the battery system. Looking at the history on the controller I have never gotten more than 17W out of the panels.


I suspect that the reading out of the MPPT is off by a factor of 10. I have shut the system down at the breaker and can see a nominal draw of 8A from the battery (-8A on the BMV 700). When I turn the system back on, it shows 1A out of the MPPT controller, but the BMV bounces up to about +1.5A. The controller is less than a year old (we took delivery in July, 5 months ago) How do I troubleshoot this?

MPPT Controllers
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

3 Answers
Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

Remove and replace the blade fuse in the bottom of the unit, if that does not help, take it back to the place of purchase and ask for warranty.

3 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

bibbjs avatar image bibbjs commented ·

Checked the fuse and it was good. No change. My problem is that it came with the boat, so I need to find out how to get it replaced.

0 Likes 0 ·
Show more comments
wkirby avatar image
wkirby answered ·

Are you able to check what the "Max charge current" setting is set to?

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

bibbjs avatar image bibbjs commented ·

WKirby, I have been looking for a setting like that, but I have not found one yet. None of the Victron Connect screens had anything that looked like Max Charge Current as a setting.

0 Likes 0 ·
bibbjs avatar image
bibbjs answered ·

WKirby, I have been looking for a setting like that, but I have not found one yet. None of the Victron Connect screens had anything that looked like Max Charge Current as a setting.


5 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

Guy Stewart (Victron Community Manager) avatar image Guy Stewart (Victron Community Manager) ♦♦ commented ·

Make sure you are running the latest version:


0 Likes 0 ·
screen-shot-2018-12-17-at-84803-am.jpg (193.9 KiB)
screen-shot-2018-12-17-at-84822-am.jpg (164.9 KiB)
screen-shot-2018-12-17-at-84830-am.jpg (149.1 KiB)
bibbjs avatar image bibbjs commented ·

OK, I missed the location of that, but it was indeed set at 15A and we are only getting 1A.


0 Likes 0 ·
bibbjs avatar image bibbjs bibbjs commented ·

So Guy, what do you suggest next?

0 Likes 0 ·
Guy Stewart (Victron Community Manager) avatar image Guy Stewart (Victron Community Manager) ♦♦ bibbjs commented ·

I would suggest isolating the panels to see what the production from each individually. Eg is it half the power, the same power, more power?

0 Likes 0 ·
bibbjs avatar image bibbjs Guy Stewart (Victron Community Manager) ♦♦ commented ·

Isolating the panels brought the power to roughly half as one would expect. We are seeing a hard max of 14W in full sun with the battery voltage down in the mid 12s.Screen Shot 2018-12-29 at 1.26.27 PM.pngScreen Shot 2018-12-29 at 1.25.43 PM.png

0 Likes 0 ·
screen-shot-2018-12-29-at-12627-pm.png (106.1 KiB)
screen-shot-2018-12-29-at-12543-pm.png (126.3 KiB)