question

pwacquiez avatar image
pwacquiez asked

Ground fault to DC (negative) on the new MultiPlus II 15000/48

Hello everyone,


It has been 2 years since my single-phase installation on an isolated site worked well with an MP2 48/10000, two MPPT250/100, CERBO...

I bought the MP2 15000 to get more single phase power (and in the hope that the latest model would be a bit quieter). I received it yesterday and installed it. When I wanted to restart my installation, the earth guardian on the direct current side (DOLD IL 5881) immediately indicated an earth fault on the negative.

Indeed, when I disconnect the earth cable from the Multiplus 15000, the tester indicates:

- 48v between the + and the mass of the MP2

- 0 v between - and MP2 ground


Otherwise, the MP2 15000 works, but it is of course too dangerous to use it as is.


What do you think ?



Multiplus-IIfeature requestfault
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.

4 Answers
Duivert NL avatar image
Duivert NL answered ·

sorry off topic:

but your AC connections on the multi are badly crimped and have dangerously open copper connections

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.

pwacquiez avatar image
pwacquiez answered ·

I suppose that the fault comes from a tin solder which makes contact between the negative and the ground or a screw passed through a negative cable inside. but it is guaranteed so I am not going to open it. it’s tedious to take it back to the supplier (~75kg), put the new one back, rewire it…

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.

sharpener avatar image
sharpener answered ·

Here is a list of what to test before sending a unit back. Although intended for distributors it might contain some clues.

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.

pwacquiez avatar image
pwacquiez answered ·

I found the problem.

There is a metal bracket behind the negative battery connection. it is in contact with one of the tin points on the electronic card.

I took a picture of the problem with a mirror and added a red arrow.

I slipped a piece of plastic to insulate it.


I don't understand why Victron did not insulate this metal support which is on ground.


img-3796.jpeg


img-3801.jpeg

img-3798.jpeg

img-3804.jpeg




img-3796.jpeg (509.3 KiB)
img-3801.jpeg (4.1 MiB)
img-3798.jpeg (4.9 MiB)
img-3804.jpeg (4.2 MiB)
7 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.

Duivert NL avatar image Duivert NL commented ·
Hi i suggest you send your conclusion and pictures to victron, thats clearly a fabrication error, could be al faulty fabricated batch of multiplus 2 15k’s
1 Like 1 ·
Justin Cook avatar image Justin Cook ♦♦ commented ·

Unrelated, but please note that neither the Blue Sea battery switch nor any of those surface-mount breakers in your install are suitable for a 48vNom system.

0 Likes 0 ·
Show more comments

Related Resources

MultiPlus-II Product page 

MultiPlus-II Manual

Multiplus-II GX Online Manual

MultiPlus-II 230V Datasheet 

VE.Bus Error codes

Faults with Victron equipment are best discussed directly with your dealer - this can be formalised with this support request form.

The feature requests topic tag can help Victron R&D find feature suggestions for products. 

There are many factors that go into the Victron product roadmap, and feedback from end-users can help.