Sprinkler Status Panel to FD&A

[John French]

Could anyone tell me why most sprinkler status panels come with de-energised relay contacts (energised on power up). i.e. when mains power is lost relay contacts change state (activating the fire alarm). I know the prefered method of connection is pressure switch but there are a lot of sites with status panels. The most resent case was a MOD base, the sprinkler system being commissioned was by a well named company, the MOD Fire Officer got very annoyed with the sprinkler company and in the end I installed more equipment to monitor the sprinkler system through the addressable FD&A and the status panel was left a box on the wall. I am wondering if it is part of BS 5306 Part 2 1990 / BS EN 12845 that the status panels have to operate like this. Unfortunately BS5839 and the fire service do not agree.

[John French]

O.K just had another instance of a status panel setting the FD&A system off. Electrical test and inspection was being undertaken within a concert hall, swimming pool, ice rink. The company undertaking the test & inspection isolate the incomming supply to one of 36 DB's to enable safe means of working. The Fire Alarm activates, the fire service are summoned via an ARC due to the fact that site security could not confirm a false alarm call, all they knew was the alarm had gone off saying sprinkler interface. After a ninety second staff alarm the building was evacuated via the P.A.V.A. When everthing had settled the site maintenance staff could not confim whether this had happened before (and as maintenance staff do "this has not happened before, I think") we were call in to investigate. The cables from the sprinkler room were traced half way across the building to a status panel located within a security room. The Fire Alarm interface was connected to a set of relay contacts within this panel. The Fire Alarm interface monitored for open and short circuit via the required E.O.L and fire resistor, but this was defeated by the status panel. This was pointed out to the maintenance staff and the fact that for the past 17 years this was the case. The next question was Solution.