Inverter mounting

[pogson6]

Hi

When mounting inverters in lofts do you use a fire rated board, mdf board or no board at all?

 

[moggy1968]

depends. I usually mount them straight on the wall if there is a robust outside wall available (brick is pretty fire proof!. failing that (double hipped roofs for example) I make a frame from 1 inch ply and 4x2 battens

 

[SolarCity]

You need to make sure the board is fire rated. Also, it is a good idea to put some kind of dampening in to avoid resonance.

 

[bumcrack]

Our assessor insisted on fire resistant material for the inverter. We used some gyproc like fireboard.

 

[sharpener]

Have been researching this topic and wondered about anti-vibration mounts or damping, what do you use please BiggsSolar??

My installer wanted 1/2 hr fire resistance, fortunately I have half a sheet of 6mm Glasroc Multiboard left over from another job to face the panel with, according to British Gypsum this meets the requirement. (Masterboard and SupaBoard are similar.) You need something as inverter heat sinks can run at 70 - 80C.

There is an SMA note (which in general does not recommend mounting on wood) here http://files.sma.de/dl/7418/HolzUnt-UEN082610.pdf

 

[SolarCity]

We use some soundproof matting that I had left over from my home studio that I built. It is also fire rated which makes it handy.

Generally we do all we can to avoid installing in this way though.

 

[pvman]

We mount onto fireboard and if we need to make a backboard for the switches etc we make this from ply and the put a smaller piece of fireboard behind the inverter.

Tom

 

[moggy1968]

To me that SMA release appears to suggest that their research showed no evidence of wood catching fire in operation

The test was conducted exclusively for the SMA inverters Sunny Boy and Sunny Mini Central. The results​

also apply for other devices using the same housings (e.g. corresponding Windy Boy, Sunny Island models).​

Self-combustion was ruled out by the expert report

and also that combustion due to an internal fault would be contained within the housing. It suggests that if mounting on wood there should be adequate airflow for cooling but does not specifically exclude mounting on a wooden wall (as against a wooden frame which would have better ventilation)(but does advise to avoid it, which is a bit of CYA I suspect)
A properly built wooden frame does not suffer from vibration

 

[sharpener]

IIRC there have been two instances of Mastervolt inverters catching fire reported on here, it would be interesting to know what they were mounted on and what the wider consequences were.

I need to replace 3 smoke alarms anyway as the rechargeable back-up batteries have died, in the course of investigating which I discovered the link wires had never been installed.

So I will replace them with wireless ones and put a 4th in the loft (on a different circuit from the inverter) along with a wireless link for the StecaGrid Connect ethernet card assuming I can get one.

 

[Chop]

I would say avoid mounting on party gable wall, encase the neighbour decides to drill into your inverter!!

 

[moggy1968]

as a result of the mastervolt post I am now reccomending customers put a smoke alarm in the loft if the inverter is up there

 

[powervan]

we fit ply then plasterboard to back of inverta! nic bloke said no good if it gets wet? well when its clamped up tight between inverta and ply im sure its not going to get all LIMP!! we have one job we got to go back to due to vibration or posh word mr biggs!! SOUND PROOF room??????????? u sure u aint got any MPs locked in there ))

 

[moggy1968]

how the hell would it get wet in the loft, unless he thinks your going to wreck the roof at the same time!!