Newlec / Bardic fire alarm panel NL5704

[Djjeff99]

Hi There
I have been asked if i can wire so as to shut off the power to a socket circuit when the fire alarm goes off .

I am thinking to do this by installing a contactor next to the DB and switch it from the fire alarm panel .
I know that the panel has a normally closed circuit in it and a common but i don't know if there is a voltage present across the contacts , or if i need to feed on to the common etc .
I need to know this so i know what voltage coil i need in the contactor .

The job is too far away just to go and test this so i was wondering if anyone knew or if they knew where i could download the manual .
The panel is a NL5704 from newlec .

Cheers
Jeff

 

[oasistechnical]

you are not advised to switch 230vac via the relay in the fire panel!!!

if you have a 24vdc supply available within the panel (i know the system you are on about, but not that well)

switch a 24v dc relay via the supply available via the relay contacts in the panel.

if you contact your local security supplier he should be able to provide you with a polarised 24 v dc relay, (these are for use with 230 v ac at the com / nc / no)

but check the loading and switch as required.

this is how we normally do it and it works ok,
what is the relay for, shutting off a supply for a socket, what is the socket feeding ?

john

 

[Lectrician]

You should use a 24vdc relay, and use this relay to power a 240v contactor of suitable rating for the sockets.

You are meant to provide a constant 24vdc supply to the relay which is broken when the alarm sounds, open circuiting the 240v coil. This is fail safe - cable fails, sockets die.

The cable to the relay needs to be FP or equiv.

Some authorites will make an effort to state that sockets must not come back on without intervention. Some people see this as resetting the alarm panel, but others see this as an extra 'reset' switch next to the contactor/fuseboard. You can do this by using a contact on the contactor as a latching contact, the reset switch in parallel with this.

You can use the 24v bell output if there is no 24vdc auxiliary in the panel, but you need to make sure you use a polarised relay with back a back emf diode, or make your own.....I will see if I can draw a quick pic.

 

[Lectrician]

This is how you would wire it if using the bell output - not sure if the Newlec has an available aux 24v (even if it does have the fire relay contacts)

If I get a spare moment I will draw one for using the fire relay, although I am sure you can figure it - use the 24v aux supply via the fire relay to switch the relay - use the com and NC of the fire relay to keep the relay energised all the time (except during fire). Then use the com and NO of the relay to do the contactor.

Untitled

• Lectrician
• 24 Feb 2010
• 1