question

pias7529 avatar image
pias7529 asked

Cerbo GX / Multiplus II - AC In shows 0 when AC power is working and generator surges up and down.

I have a multiplus ii with a cerbo gx connected. Currently i have a lifepo4 lithium ion battery bank and a honda generator (running through a transfer switch) connected for power. I have an ac panel connected with an outlet wired to it running a fan and light. All victron components are up to date on firmware on this date. I have changed the name of the ac source to Shore Power. The battery bank runs everything just fine, and the generator powers the AC loads just fine. However, when the generator is running the cerbo is not showing any AC IN and the generator surges up and down from 0 to rough1300 watts evry 30 seconds or so? Does anybody have any thoughts on how to resolve these issues?

cerbo gx
2 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.

jacobjned avatar image jacobjned commented ·
Please verify on the Cerbo GX, under settings > System setup > reconfirm the "AC input 1" is what you have selected as Shore power and NOT "AC input 2".
0 Likes 0 ·
pias7529 avatar image pias7529 jacobjned commented ·
Thanks for contributing. AC input 1 is set to Shore power. I only have 1 hot wire (120V), so AC input 2 is "Not available".
0 Likes 0 ·
2 Answers
JohnC avatar image
JohnC answered ·

@pias7529

Take a look through this.. https://www.victronenergy.com/live/multiplus_faq

Dynamic Current Limiter is almost always necessary with small gensets. Try also limiting the input current until you get a better feel for what's happening.

Some inverter regulated gensets can also trip themselves and reset, so ensure that's not happening.

Bear in mind that the genset has to wear both the loads and charge current when switched in, and this can be substantial.

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.

pias7529 avatar image
pias7529 answered ·

Thanks for the help. DCL is checked, and the generator supplies power just fine when the battery bank is disconnected. When the battery bank is connected, the generator cycles up and down 0-1300W repeatedly. Also, the display always shows 0 AC In even though there is obviously AC flowing through the MultiPlus II.

2 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.

derrick thomas avatar image derrick thomas commented ·
What you describe sounds like the generator is overloading when the multi tries to connect to incoming ac or start charging. Have you lowered the input limit? Tried turning off eco mode on the generator?
0 Likes 0 ·
pias7529 avatar image pias7529 derrick thomas commented ·

I have turned off eco mode and have the input limit to set to 15 amps (which the generator can easily handle). I am thinking that since the incoming AC power is displaying as 0 that the input is not actually being limited. I have set the input limit to 10 amps and the generator still surges higher than that. Do you (or anyone) have any idea why the Cerbo is not seeing/displaying any AC input when the input is clearly flowing through the inverter?

0 Likes 0 ·