Are string inverters safe during a house fire ???

[SolarCity]

I still don't see the hazard. Spraying water onto the DC cables poses next to zero risk of shock as far as I can make out.

If all the insulation melts off and and for an unfortunate fireman to actually get hold of both ends of the string would require him to be below a collapsing roof and then be a victim of the most apalling luck possible.

 

[moggy1968]

never let it be assumed that H&S was related to logic!!

 

[mdovey]

This is probably an argument for keeping the inverter as close to the panels as possible, and having a long AC run if necessary rather than a long DC run, in order to keep the amount of cables still live when grid power to the building has been shut down to a minimum.

 

[mdovey]

The amount of smoke bellowing out of the soffit is bound to cause some shading issues, so the inverter probably won't be running.


I'll grab my coat on the way out......

Also the fire will be heating the panels which will significantly reduce their efficiency!

 

[mdovey]

Check this out Firefighter's Safety Switch - Sibert - automated equipment manufacturer and supplier of process consumables

Googling about, one of the suggested dangers is that a firefighter might get an electric shock if they put an axe (or foot) through a solar panel. The above switch isn't going to prevent this.

Also, what stops the fire damaging the components which enable the switch to be controlled remotely?

 

[moggy1968]

the length of DC run won't affect things, if they won't touch it they won't touch it.
Even if a fireman is stupid enough to put his axe through a panels their voltage is below 50v and I can't see you getting a shock off the internal components of a panel under any circumstances.

 

[mdovey]

Even if a fireman is stupid enough to put his axe through a panels their voltage is below 50v and I can't see you getting a shock off the internal components of a panel under any circumstances.

You may have guessed by the fact I said "suggested dangers" that I wasn't entirely convinced...

 

[SibertSolar]

You're quite right mdovey, you can't mitigate against every scenario, this unit from Santon only disconnects the feed from the array, it doesn't stop the array from producing. Mind you, a foot or axe through a panel will most likely just cause that panel's bypass diodes to kick in anyway....

As fare as fire damaging the components that enable the switch to be controlled remotely, the design is fail-safe so if the signal cable is damaged the unit will disconnect, there is a UPS fitted into the main disconnection unit.

 

[edexlab]

My Brother is a fireman and we had a conversation about this after I'd told him about a study I read on fire and Pv systems in Germany ,the fire service had tried to cover panels with foam,to shade panels only trouble is it slides off they also looked at other methods the answer came back was to fit an external isolator, last i heard it was expected to become a requirement

however my brother wasn't overly concerned and said that they have directed high pressure water at 11kv transformers on fire which were still live, obviously not an ideal situation to find yourself in but they assess the risk and act accordingly
Also he'd not heard of any kind of training or information regarding Pv being made available to the fire service as yet.