Victron MPPT 100/20 upside down?

[goeasy123]

Is there a reason the the manual says mount it with the terminals at the bottom?

A post on the Victron forum says.... 'Moving upside down is risky: it makes it easy for water to flow into the controller, destroying the controller and possibly putting PV voltage onto the battery output with it' and 'water will "wick" inside the plastic sheath, along the wire strands. Capillary action...'

This sounds like nonsense to me.

In my installation the the PV cable runs for some length below the level of the controller and through a switch, so water is not going to get in through the PV cable.

Is there another reason it can't be upside down?

 

[penfold]

It's not nonsense, it happens. The housing has a large orifice on the bottom where the cables come in, if you mount it upside down it will be vulnerable to drips and falling debris, risking shorts. These risks can be mitigated but it's a lot easier to just mount it the way Victron have designed it to be mounted.

 

[Baggywrinkle]

It may also be that the device circuit board is designed to be mounted cables down, i.e. internal cooling works optimally when mounted as specified. Unfortunately, while manufacturers specify how their devices should be mounted, they don't usually say why, so self assessing the risk of not following the manufacturers recommendations is difficult.

Warranty may also be affected. If it stops working they may charge for repairs when they open it up, and find evidence of it being mounted upside down (settled dust, signs of liquid ingress, debris etc.)

 

[RichardS]

Is there a reason the the manual says mount it with the terminals at the bottom?

A post on the Victron forum says.... 'Moving upside down is risky: it makes it easy for water to flow into the controller, destroying the controller and possibly putting PV voltage onto the battery output with it' and 'water will "wick" inside the plastic sheath, along the wire strands. Capillary action...'

This sounds like nonsense to me.

In my installation the the PV cable runs for some length below the level of the controller and through a switch, so water is not going to get in through the PV cable.

Is there another reason it can't be upside down?

I think you've misunderstood. If it's mounted upside down then the final run of cable is from above and runs down vertically into the controller ..... which is exactly what water does and the cables will help it.

Richard

 

[PaulRainbow]

From the Victron installation manual:

Mount vertically on a non-flammable substrate, with the power terminals facing downwards. Observe a minimum clearance of 10 cm under and above the product for optimal cooling.

But what do they know ?

 

[lustyd]

I think you've misunderstood. If it's mounted upside down then the final run of cable is from above and runs down vertically into the controller ..... which is exactly what water does and the cables will help it.

Richard

I suspect OP's point is that water doesn't generally just appear out of thin air. Obviously there's condensation to deal with, but other than that if it's dry then water isn't an issue. The question then becomes what else would be a problem.

 

[goeasy123]

I suspect OP's point is that water doesn't generally just appear out of thin air. Obviously there's condensation to deal with, but other than that if it's dry then water isn't an issue. The question then becomes what else would be a problem.

Exactly. In my installation water is only likely to get into the MPPT shortly after the boat sinks.

If I were to ask the designer why it needs to be right-way-up and how critical it is I wonder what he would say?

 

[RichardS]

I suspect OP's point is that water doesn't generally just appear out of thin air. Obviously there's condensation to deal with, but other than that if it's dry then water isn't an issue. The question then becomes what else would be a problem.

Obviously none of us want to find water dripping from a leaking stanchion base or window but it does happen on many/most boats eventually and if that drip happens to hit the upside down mounted controller or it's cables where they enter, then the controller will be toast.

I can't really believe that we're even discussing this.

Richard

 

[PaulRainbow]

Exactly. In my installation water is only likely to get into the MPPT shortly after the boat sinks.

If I were to ask the designer why it needs to be right-way-up and how critical it is I wonder what he would say?

He would say:

Mount vertically on a non-flammable substrate, with the power terminals facing downwards. Observe a minimum clearance of 10 cm under and above the product for optimal cooling.

Water aside, there are also possible cooling issues, electronics are often designed to be installed in a particular orientation for optimal cooling of internal components.

Why do you need to install it upside down ?

 

[lustyd]

I think the MPPTs tend to have pretty generic vertical cooling with a heat sink so I don't think there's much that would affect that. I certainly don't disagree with the sentiment of following instructions, but the question seems valid enough to me to wonder what would happen. Victron cable connectors are quite difficult to use in tight spaces so I can certainly see situations where upside down might be preferable for access reasons. If it was me though I'd probably mount the cables before mounting the controller in that case

 

[lustyd]

Obviously none of us want to find water dripping from a leaking stanchion base or window but it does happen on many/most boats eventually and if that drip happens to hit the upside down mounted controller or it's cables where they enter, then the controller will be toast.

I can't really believe that we're even discussing this.

Richard

Houses suffer from much the same if not maintained, I still have a consumer unit though and feel confident enough that it won't suddenly drown for no good reason. If you can't imagine a place on a boat not prone to leaks, you might need a new boat!

 

[RichardS]

Houses suffer from much the same if not maintained ....

Seriously?

Richard