elevator recall wiring conventional fa system
Could some one give me a rundown on how a conventional system is wired for elevator recall... (not addressable)
I'm looking for non addressable system wiring.
Originally Posted by jusme123
I talk to people about this all the time. If you follow the letter of the Fire Alarm Code, I don't know how to do it properly with most conventional systems.
For one, only the elevator lobby, shaft and equipment room smoke detectors are allowed to recall the elevator. Depending on how many zones your panel is and how many floors the building is you can run out of zones quickly because each elevator lobby smoke might require itís own zone.
The most important hurdle is the code requirement for the relays to be within 3 feet of the device or circuit it is controlling. This normally means the relays need to be mounted in the elevator machine room and is best done with addressable relays. If your conventional panel has a relay card that can be remote mounted and supervised then maybe you can use a conventional panel.
Some jurisdictions allow the use of relay base smoke detectors to recall the elevator. In that case you could use a 4 wire smoke detector for the lobby smokes and trip the alarm panel with the alarm relay and recall the elevator with the auxiliary relay. The problem with this is the relays are not within 3 feet of the elevator controller. There is a chance the wiring could be compromised between the detector and elevator controller so that the alarm panel would not be aware of the fault and the elevator could not be controlled by the detector.
If you cannot remove an existing conventional panel at this time, I would recommend installing an addressable panel for the elevator recall and have it monitored by the conventional panel.
You can use a notification appliance circuit to accomplish elevator recall AND have supervision of the relay by using this. If you have to use more than three relays, it could get a little tricky because then you have no way to operate notification appliances as most conventional fire alarm panels that I'm familiar with do not have more than four (4) NAC's. Unless you can extend an existing NAC to the elevator controller, and as long as the added current draw doesn't compromise the notification appliance operation.
Originally Posted by dhalleron
I have succesfully done this at a couple of locations.
I've seen people use the polarized relays to be controlled by a NAC circuit like gadfly56 mentioned. I have been told some inspectors get picky and say a NAC circuit is a Notification Appliance Circuit, not a Relay Circuit and they won't allow a relay on that circuit.
In some applications such as door lock release if you use a non latching relay on a silenceable NAC circuit, then the doors will lock back when the fire department hits alarm silence on the panel. They tend to not be very happy when that happens.
It can be done on a conventional panel, just be careful of all the limitations and potential problems.
I have 4 wire smoke detectors with a relay, it should be simple that way when the smoke goes into alarm it will trip the function required depending on where its located. primary or alternate recall.
Would i need to have a separate zone for the elevator recall?
How would i trip the shunt assuming i have a 4 wire heat detector in the machine room?
You need to slow down a bit before you get into trouble here. Unless the 4-wire smoke detector is located within 3 feet of the elevator controller the AHJ is unlikely to allow it to control the elevator recall. Same for your dual circuit heat detector. If you have more than one floor, not more than one smoke detector can possibly be within 3 feet of the elevator controller. Of course, if you have only one floor you don't have an elevator.
Originally Posted by bgelectric
Before addressable panels came along, we all lived with the limitations of conventional panels. Once they became cheap enough, NFPA 72 was revised to require that the fire alarm panel relay be within 3 feet of the controlled device. If you already had elevator recall using conventional devices you could keep it or repair it. For new installs on a conventional panel, you have to kludge it the way I described and hope you have the NAC's you need. If you need shunt as well, that means you have at a minimum a heat in the shaft and a heat in the elevator mechanical room. Now it's just getting ridiculous to do this with a conventional panel. The amount of time you'll spend trying to create this Frankenpanel may satisfy your sense of inventiveness, but for the dollar value of your time you could give the customer a small addressable panel.
If you need primary and secondary recall for a multistory building, the best solution is an addressable panel, even just a small one like the Silent Knight 5808 would do. Use it for elevator service only. Then you can accomodate recall, shunt, and fire hat as well.
couldnt you use a smoke detector with a built in relay base such as the system sensor B116LP, then go to a relay mounted in the elevator machine room or where ever the elevator controls are located which would then be wired to the primary recall/secondary recall/firehat/shunt inputs of the elevator controls? bring AUX power to the detectors wired in as N/O with the relays so that an activation would close the contacts thus sending power down to the relays mounted near the elevator equipment that would then drive the fire functions of the elevators?
food for thought
In RI we have an amendment to the code, we capture the elevator on any alarm not just the lobby detectors.
This is why, we require smoke detectors to be installed in all corridors typically there are installed between 30 -42 feet apart, the idea behind recall is to not have people exit the elevator under an alarm condition on the fire floor.
If there is a smoke detector installed 30 -42 feet away from the lobby smoke detector and it is not part of the recall matrix you could potentially be putting people into the fire, think about it the elevator recalls, door opens and exit pathway is full of smoke, you cant get back on the elevator its locked out on that floor.
Anyway, conventionally per national standard NFPA 72, your going to be running a lot of wire, because you will now need to send 3 signals to the elevator controller, 1 primary floor, 2 secondary floor and 3 is activation of elevator mech. room, and or top of shaft.
The 3rd signal is often missed it is very important what it does is flash the fire helmet on the inside of the elevator car, the fire service is trained to know if you are operating the elevator on fire service during an alarm and the hat begins to flash you need to get out, there is a condition in the elevator mech. room or in the shaft, its no longer safe to be using the elevator.