question

jgilk avatar image
jgilk asked

12/120/3000 Multiplus trips Main Shorepower in breaker

Had professionals install two 12/120/3000 Multiplus’ in parallel. All worked for a week and then randomly main shore power in breaker tripped and continues to trip instantly if shore power is connected. Contractors said it was the type of Shorepower in breaker and that it didn’t “filter” some noise that caused Multiplus to trip. They installed $500 of new main shore power in breaker/panel/box. Everything worked great, again, only for a week. Now Main Shorepower in breaker continuously trips if Shorepower and Multi’s are both connected. At least the new breaker/panel has an indicator that shows leakage fault when it trips. I have an emergency switch I can turn that disconnects Shore and Multi’s so I can stay connected to shore power. But need to try and figure this out without contractors as they have lost my confidence. Puzzling part is why everything worked fine for a week then stopped both times. Any thoughts?

Multiplus-II
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.

boekel avatar image boekel ♦ commented ·
Do you have a diagram of the installation?
0 Likes 0 ·
jgilk avatar image jgilk boekel ♦ commented ·

Here is a diagram of the installation.

0 Likes 0 ·
1549256400524.png (19.8 KiB)
Guy Stewart (Victron Community Manager) avatar image Guy Stewart (Victron Community Manager) ♦♦ commented ·

Can you also post a labelled photo of the bypass switch panel wiring?

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

The bypass switch doesn’t have a panel. It is just a Blue Seas Shore Power/Generator switch that contractors installed that disconnects Multiplus from Shore Power when turned so that I am able to use shore power without manually disconnecting Multiplus wiring.

0 Likes 0 ·
0a9b6a32-67f0-4ef8-ac06-9d494dcf02bc.jpeg (276.5 KiB)
jgilk avatar image jgilk jgilk commented ·

It’s relabled as “Off, Normal & emergency.” Off is obvious, Normal allows Shorepower to flow through Multiplus to use charge, whereas the emergency setting removes the Multiplus from the Shorepower connection wand allows Shorepower to work independently. Again, initially everything worked for a while and then our Schneider brand main Shorepower ELCI breaker started tripping every time the charger portion of Multiplus kicked on. Contractors said they were told by Victron that the ELCI wasn’t compatible and needed to switch to the BlueSeas ELCI which they did. Everything again worked for a few days then the issue arose again. Now they say Victron is telling them to switch to an Airpax ELCI.

0 Likes 0 ·
Show more comments
4 Answers
Paul B avatar image
Paul B answered ·

There is a ground relay in the multiplus units that connects the neutral to earth. this is normally ON you could try turning this OFF.

However you need to research the dangers in doing so and why its there in the first place . so be very careful in doing so.



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.

Pat Davitt avatar image
Pat Davitt answered ·

This is a common problem, not just with Victron, but all inverter/chargers that have a Neutral/Ground Bond transfer switch. You don't have to turn off the AC input to the inverter/charger, but you do have to turn off the AC output from the inverter/charger.

Below is a schematic of my system showing the By-Pass wiring.

Pat


project-schematic.jpg (4.5 MiB)
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.

jgilk avatar image jgilk commented ·

Having a switch to turn off the a/c output from the Multiplus is an in-elegant solution to an elegant Victron setup. Not to mention you lose features the Multiplus offers by doing this, such as its “assisting” feature.

0 Likes 0 ·
Pat Davitt avatar image Pat Davitt jgilk commented ·

The problem with that is that you are dealing with an Inverter/Charger. When you disconnect the AC input from the Multiplus it goes into Inverter mode and provides AC output. When you also have a second AC source (Shore Power) feeding the loads it causes all sorts of problems. The only way the Multiplus can use the "Power Assist" is if it knows the characteristics of the other AC source, i.e. the AC source is input into the Multiplus. To work properly together, the two AC sources must have their voltage, wave form, and phase angle synchronized. That is part of the Power Assist functionality.

I know this is a little complex, but I don't know how else to phrase it.

Pat

1 Like 1 ·
jgilk avatar image jgilk Pat Davitt commented ·

That’s what we are running into, the AC sources have been synchronized. Also, the main Shore Power ELCI only trips when the charger aspect of the Multiplus kicks in. Which means the inverter side AC our would be off (on standby to assist). Just seems this setup shouldn’t be that difficult to configure where everything communicates together like it should.

0 Likes 0 ·
boekel avatar image
boekel answered ·

Jgilk, you really have to post the diagram of the bypass switch, the way you're describing it it sounds like you connect the output of the inverter to the shorepower, that's a no-go,

Most elegant solution would be to be able to put the multiplus in 'passthrough mode' but I don't know if that is possible.

if you want to 'bridge' the multiplus you have to disconnect the output, otherwise you're feeding the multi from the AC-out side.

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.

Paul B avatar image
Paul B answered ·

This is a stab in the dark, just some thoughts and maybe some other directions to go and look at.

1. Another possible cause could be ground loops, you mention that it only happens when you are using the battery charger only. as this is the DC side, MAYBE this is giving some form of issue in that marina in relation to another boat thats got some electrolysis issue. and then, somehow causing a inbalance in RCD on the dock.

2. you could try a Isolation transformer as this will Isolate you completly

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.