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Topic Title: Fixed Wire Testing
Topic Summary: Fire Alarm requirements
Created On: 15 February 2013 09:47 AM
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 15 February 2013 09:47 AM
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andrewmac

Posts: 237
Joined: 14 April 2004

Can someone please advise as to the requirements for fixed wire testing of a fire alarm system.

i.e.

Frequency/ responsibilty/ range of tests required and any other relevant information...

thanks
 15 February 2013 10:42 AM
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OMS

Posts: 19676
Joined: 23 March 2004

Clause 38 of BS 5839-1 will give you most of the answers

Point 26 in clause 39.2 will also be relevant.

In terms of the ongoing electrical tests required over the system life, then it depends on what the system itself monitors. Most systems will generally monitor for short circuit conditions and open circuit conditions (as well as earth fault in some cases).

Essentially, electrical testing of cables, is then subject to risk assessment and testing derived from that.

Refering back to BS 7671, Section 110.1.3 should tell you that the fire alarm system is also an installation and as such, 622.1 should tell you that the extent of testing shall be determied giving regard to the type of installation and the environment.

As a broad rule of thumb, I tend to work on the basis that detection etc has a finite life (say 10 - 15 years) so when being swapped out, that's the sensible time to electrically test the cabling

Regards

OMS

-------------------------
Failure is always an option
 16 February 2013 08:30 AM
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MrP

Posts: 840
Joined: 24 March 2006

As a basis I would want continuity polarity and IR with a verification sheet to accompany it would do no harm all equipment and devices removed, my F/A subcontractor on site thought that letters O and K would suffice.
MrP
 17 February 2013 01:33 PM
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hertzal123

Posts: 303
Joined: 26 August 2007

Mr P,
With a 2 wire system with pcb,s in the bases,would all bases have to be bypassed and what voltage would you IR test at?
Hz
 18 February 2013 05:25 AM
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MrP

Posts: 840
Joined: 24 March 2006

HZ
Depending on the type of system cabling selected, most common FP100/200/400 MICC 600v cable whilst the requirement for IR for a SELV circuit is 250v I would have no problem with a 500v test depending on the cable type, your verifying that the plastic and neoprene bits are in place, your checking the insulation (the plastic bits) of the cable nothing more
Whether 1v or 500v All equipment and devices must be removed or isolated to conduct the IR test
Now if its an existing sytem as OMS states most modern panels monitor the system
Depending on your scope of works would I want to dismantle the system, if I didn't have to probably not.



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