Do I Need a Special Relay for Smoke Detector Sounders

[upstatemike]

I am planning the wiring for the 30 smoke detectors I am going to be hooking to m M1 and I have a question about the polarity reversal relay used to set off all of the sounders during a fire alarm trip. It looks like a simple polarity reversal configuration triggered by the fire alarm output, so why do I need a special relay from ESL or whoever? Can't I just use some regular 12V realys and wire up the same thing myself?

 

[Spanky]

The short answer: it is a double throw, double pole relay that reverses the polarity of the current running to the smoke detectors.

The long answer: your relay is not UL listed for a fire reversing relay application....!

Go figure!

 

[upstatemike]

The short answer: it is a double throw, double pole relay that reverses the polarity of the current running to the smoke detectors.

The long answer: your relay is not UL listed for a fire reversing relay application....!

Go figure!

I will have to use a supplemental power supply for that many smokes, so won't that kill the UL certification anyway? Or is there a particular power supply that is UL certified for smoke detector power? (I was planning to use a Moose HCP12 2 Amp supply)

 

[upstatemike]

Also, how are folks hooking up the sounder relay? It looks like output 2 would trigger the sounders on both fire and burglery. Can output 3 be set to trigger on fire only? Does UL require you to use a supervised output for the fire alarm sounder relay?

 

[Digger]

Also, how are folks hooking up the sounder relay? It looks like output 2 would trigger the sounders on both fire and burglery. Can output 3 be set to trigger on fire only? Does UL require you to use a supervised output for the fire alarm sounder relay?

System Sensor makes a UL Listed reversing relay that is pretty popular. There are a few ways you can trigger it (bell output or a trigger output from the panel).

Altronix makes some nice UL Listed Fire Alarm Power Supplies. They are not cheap but they are not overpriced either in my opinion. I beleive they also have a lifetime warranty (a real one). Technically they are a competitor of the company I work for but its a good product and company and I reccomend them to our customers if we do not have something equivalent at the moment.

At work I am working on 2 or 3 Fire Alarm Power Supplies to get UL Listing. It is a VERY long process. It took 7 months to get a price and number of samples needed for testing. Then another 5 months to tell me they need more samples then they asked for and they still have not run a single test (and wont for months probably). The cost is about $25K for the power supply evaluation based on 2007 prices so that makes the end user price higher. I dont expect to get a UL Listing for another 6 months to a year at this rate. Luckily I was able to get this as a priority evaluation otherwise it would take even longer (Spanky knows how it is with UL testing).

 

[upstatemike]

System Sensor makes a UL Listed reversing relay that is pretty popular. There are a few ways you can trigger it (bell output or a trigger output from the panel).

Altronix makes some nice UL Listed Fire Alarm Power Supplies. They are not cheap but they are not overpriced either in my opinion. I beleive they also have a lifetime warranty (a real one). Technically they are a competitor of the company I work for but its a good product and company and I reccomend them to our customers if we do not have something equivalent at the moment.

At work I am working on 2 or 3 Fire Alarm Power Supplies to get UL Listing. It is a VERY long process. It took 7 months to get a price and number of samples needed for testing. Then another 5 months to tell me they need more samples then they asked for and they still have not run a single test (and wont for months probably). The cost is about $25K for the power supply evaluation based on 2007 prices so that makes the end user price higher. I dont expect to get a UL Listing for another 6 months to a year at this rate. Luckily I was able to get this as a priority evaluation otherwise it would take even longer (Spanky knows how it is with UL testing).

I see the system sensor relay detects the fire bell cadence to prevent activation on steady burgler output. Once you reverse the power to the detectors does the one in alarm reset so you don't know which one set things off??

Also curious if it takes so long for UL testing, what do companies do with high tech stuff that only has a 1-2 year projected lifespan? Seems like the technology would be obsolete before UL approval was ever secured!

 

[Digger]

System Sensor makes a UL Listed reversing relay that is pretty popular. There are a few ways you can trigger it (bell output or a trigger output from the panel).

Altronix makes some nice UL Listed Fire Alarm Power Supplies. They are not cheap but they are not overpriced either in my opinion. I beleive they also have a lifetime warranty (a real one). Technically they are a competitor of the company I work for but its a good product and company and I reccomend them to our customers if we do not have something equivalent at the moment.

At work I am working on 2 or 3 Fire Alarm Power Supplies to get UL Listing. It is a VERY long process. It took 7 months to get a price and number of samples needed for testing. Then another 5 months to tell me they need more samples then they asked for and they still have not run a single test (and wont for months probably). The cost is about $25K for the power supply evaluation based on 2007 prices so that makes the end user price higher. I dont expect to get a UL Listing for another 6 months to a year at this rate. Luckily I was able to get this as a priority evaluation otherwise it would take even longer (Spanky knows how it is with UL testing).

I see the system sensor relay detects the fire bell cadence to prevent activation on steady burgler output. Once you reverse the power to the detectors does the one in alarm reset so you don't know which one set things off??

Also curious if it takes so long for UL testing, what do companies do with high tech stuff that only has a 1-2 year projected lifespan? Seems like the technology would be obsolete before UL approval was ever secured!

The detector stays in alarm (red light flashes etc so you can identify the detector that tripped the alarm).

Not all products take this long at UL. I worked there for 12 years and often evaluated products in 2 months or less. Fire Alarm equipment categories take FOREVER. There are a lot of internal problems at UL in these categories that still need to be addressed.

 

[upstatemike]

The detector stays in alarm (red light flashes etc so you can identify the detector that tripped the alarm).

OK so I will see the detector that initiated the alarm but then I will need another relay tied to the smoke power output on the panel to interrupt the power from my auxiliary power supply when I do a smoke reset, right?

 

[Digger]

The detector stays in alarm (red light flashes etc so you can identify the detector that tripped the alarm).

OK so I will see the detector that initiated the alarm but then I will need another relay tied to the smoke power output on the panel to interrupt the power from my auxiliary power supply when I do a smoke reset, right?

The smoke detector power VSAUX or SAUX (I cant remember at the moment) alerady has a relay onboard and when you do a smoke detector reset will interupt the power for about 5 seconds so I would try and power the detectors themselves from there. The siren in the detector will stop when you silence Output 1 and the siren power can come from the aux supply.