Victron Smart Solar Mppt Installation.

[TSB240]

I have read the manual but can't find the answer.

Is it possible to bridge the battery and the load negatives for any period of time or will it damage the controller?

I know it is definitely no for the SP connection!

I was hoping to connect our fridge to either the load circuit or battery with a single pole three position on off on toggle without bothering the negative side.

Using a two pole switch is possible but messy from an installation view.

I could disconnect the battery negative from the load circuit by turning the main negative Isolator off.

 

[andsarkit]

Can you check with an ohm meter to see if the load and batt terminal negatives are connected inside the Victron? If there is a short between them you should be OK. If not, I would check with Victron or ask the question on their community.

 

[Alan S]

It's actually likely that the positives are commoned and the switching is done on the negatives. Easy to check with a multimeter.

 

[[70521]]

Quietly scratching my head here wondering why you want/need to do that?

 

[TSB240]

Quietly scratching my head here wondering why you want/need to do that?

I was thinking ahead of using or leaving our boat off grid for a week or more with just the fridge/freezer powered by the solar load.
A bad week in Wales with horizontal rain and heavy cloud cover could risk depleting the lead acid house bank more than I would like. I would prefer for longevity that the house bank is never more than half depleted.
This is best done with the load voltage cut off and restart in operation built in to the Victron Smart Solar MPPT controller.

I am 99% sure that the operation of this is will be messed up if the load and battery negatives are permanently bridged.

It's easy whilst on board to switch the fridge freezer off before going to sleep. Remembering to turn it off and on isn't getting any easier with old age?

 

[[70521]]

I was thinking ahead of using or leaving our boat off grid for a week or more with just the fridge/freezer powered by the solar load.

Thanks, that makes sense.

I have friends who sailed from France, through the Panama Canal, down to South Georgia, then back up the Atlantic to Ireland, Scotland and Norway all without a fridge. I rarely turn mine on and when I fill it with frozen stuff.

 

[TSB240]

It seems the MPPT load output is incapable of providing a supply to a fridge or any item with a high inrush current( eg Diesel warm air heater.)
It will either end up rapidly switching on and off or blowing the main fuse of the MPPT controller. It is really only designed for light loads like phone charging.
You can protect a battery bank from depletion by these loads by adding a battery protect unit. This can be wired to the MPPT controller with just a thin control wire.
It won't measure the current load but it will stop unwanted deep discharge.
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