Discuss Shunt trip in a domestic CU? Looking for a complaint way of remotely switching off power in the Electrical Forum area at ElectriciansForums.net

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Hi. A thought of a domestic fire in my house terrifies me, so I installed a really sophisticated fire alarm in my house. This system optionally can even turn off the gas valve (it has a motorized arm which is installed on the main valve) and switch off electricity in case if the fire is detected in unoccupied house. It switches off electricity by sending a LV or 230V pulse through a wire which should be connected to a "shunt trip".
I contacted a local sparky, an older but very nice guy, unfortunately he couldnt really understand what i want to achieve and he has never seen such fire alarm in his life. After a discussion he suggested me that i would need a contactor installed on every circuit i want to protect this way, unfortunately this is not a feasible solution as i wouldnt have enough space in my CU.
Ive done some research online looking for a domestic shunt trip, but while such devices are widely available in EU i couldnt find any in the UK. Im assuming that's because British BR simply dont allow such devices to be installed in a domestic environment. Am i right here? A friend of mine, also an electrician but living in a different country, suggested me that i need a contactor which would forcefully trip my RCDs, but this doesnt sound like a safe solution to me (after all, i want to protect my house from fire instead of creating a starting point). Any advice how this can be installed? The solution needs to be "complaint enough" to get someone qualified to actually install it and sign it off.
 
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Gas supplies are normally shut off by way of an auxiliary circuit from a Part 1 fire alarm control panel which closes a solenoid valve. As for shutting down your electrical systems, pointless and may leave at risk as the system will isolate your lighting, very handy at night unless younintend to fit emergency lighting.
 
I may consider fitting unmaintained emergency lighting in a corridor, if it's gonna be needed, however the alarm should only switch off electricity if house is unoccupied (it has presence detection).
 
How does the presence detection work? Movement? If you've all been sleeping for hours, the panel may well think the property is unoccupied and cut the power.
 
I can understand the gas shut off that is common practice but not the electric system, it seems pointless.
 
So the fire alarm has detected fire in the unoccupied house.
It's turned off the power and gas.

The fire is still burning.
 
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Describe your sophisticated fire alarm system.
 
How about running the supply to the consumer unit through a 100A relay, and have the fire alarm panel control the relay, that way instead of putting a contactor on each circuit, you have one in front of the main breaker.
 
is that sophia's sister?
Shunt trip in a domestic CU? Looking for a complaint way of remotely switching off power {filename} | ElectriciansForums.net
 
how will the fire alarm continue to work without leccy? is it paraffin powered?
 
Hi. A thought of a domestic fire in my house terrifies me, so I installed a really sophisticated fire alarm in my house. This system optionally can even turn off the gas valve (it has a motorized arm which is installed on the main valve) and switch off electricity in case if the fire is detected in unoccupied house. It switches off electricity by sending a LV or 230V pulse through a wire which should be connected to a "shunt trip".
I contacted a local sparky, an older but very nice guy, unfortunately he couldnt really understand what i want to achieve and he has never seen such fire alarm in his life. After a discussion he suggested me that i would need a contactor installed on every circuit i want to protect this way, unfortunately this is not a feasible solution as i wouldnt have enough space in my CU.
Ive done some research online looking for a domestic shunt trip, but while such devices are widely available in EU i couldnt find any in the UK. Im assuming that's because British BR simply dont allow such devices to be installed in a domestic environment. Am i right here? A friend of mine, also an electrician but living in a different country, suggested me that i need a contactor which would forcefully trip my RCDs, but this doesnt sound like a safe solution to me (after all, i want to protect my house from fire instead of creating a starting point). Any advice how this can be installed? The solution needs to be "complaint enough" to get someone qualified to actually install it and sign it off.
Of course you coulsalways install a suitably sized Contactor with N/O contacts with a coil suitable to the output rating of your sophisticated Fire alarm panel installed into the input to your consumers Unit / Distribution Board.
So that when and if the fire alarm detects a fire it will energise the coil and trip the supply to the the CU/DB this of course will also, in the process of a fire tripping the Contactor will shut the supply to the F/A panel Off rendering it useless. unless of course it has a DC back up supply via batteries, this will negate the need to install contactors/ relays in all the circuits, in the mean time, depending on how your doors windows etc are configured will go failsafe and unlock all exits and entries, ensuring your property is open to looting, by undesirables that may live in your area. Not sure how compliant this will be with regards to BS7671 and all the othe fire and escape regulations that may have been broken.
I respectfully suggest that you take advantage of the numerous Smart Home Companies that exist. Good luck in your endeavours. Kapla.
 
I would be extremely interested in the means of isolating the gas supply,in a domestic arrangement,the approval and the compliance,with appropriate authorities.
I did notice that the OP stated "optionally"...
 
What about a dp isolator on the tails between the cut out and the board, dp switch and contactor before the board in n/c position, in emergency coil enegergised contactor opens and kills power
 

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