Newbie With Questions :) TIA

Hi Guys, I’m really new to fire panels and have a couple of questions, I appreciate they may seen silly or basic to some people:

[list][/list]On an addressable panel, how does the panel know what device has gone into fire? What in the device communicates this/how does it transfer that data back to the panel?
[list][/list]Non-latching meaning (e.g non-latching relay, non-latching zone configuration)
[list][/list]Loop processor card - 1 per loop? What is the point of it?



C-Tec CFP:
[list][/list]Difference/examples between Aux/Fault/Input/Output terminals on this particular panel.
[list][/list]What one sends panel into fire and what one in to fault? For example, a Gent Xenex has a common fire switch that is normally open. Why does this panel have NO or NC options for fault?





Gent Vigilon:

Clean contacts - Only for plant equipment? (e.g. stopping lifts when in fire) Do they need to be programmed to shut a lift down for example or does it just automatically do it once connected?



TIA :slight_smile:



Part 2 from second post



Me again, back with more questions that again may be simple:


  • Why would a sounder base have a relay attached? What would it be for?
  • What is a pulsed relay? Does it just mean constantly monitored?
  • On a conventional panel, does the EOL resistor connect the pos and neg in the circuit?
  • Monitored output meaning? 0v?
  • Are “Master Alarms” just sounders?
  • Why would you delay outputs? Is this just to give time in case of a false alarm?
  • Plug in card just a loop processor card?
  • With class change to another panel (e.g. in schools) can the other panel go into fire, or do just the sounders go off? Dependent on panel?
  • On panel terminals, is 24v always pos and 0v neg? Is this where batteries go?
  • What is a 2 way device?
  • On an addressable panel, does the Loop literally loop back? So there would be 4 inputs on that terminal? 2 In and 2 out?



    TIA :slight_smile:

Sounds like you may want to search through the forums for some detailed info. There’s a whole section dedicated to the explanation of system terminology and the in-depth various theories of operation. I’ll provide some brief answers here as a starting point so you can research specifics. There is a lot of great information in the forums.


  1. On an addressable panel, input devices communicate over a 2-wire SLC (signaling line circuit). The circuit is connected to a loop controller at the panel. The loop controller “pings” every device on the loop and asks for a status report. Devices signal back “Normal,” “Alarm,” or “Fault.” Exactly how this communication happens/what type of data is passed greatly depends on the manufacturer. On modular systems (Simplex or EST), the loop controller is a separate datacard. On smaller systems (Fire-Lite/Silent Knight), the loop controller is built into the motherboard of the panel.


  2. A “Latching” event means that once a trigger event occurs (pull station activated), the panel will “latch” into alarm or supervisory until a full system reset is performed. Non-latching means that as soon as the trigger event stops occurring (pull station reset), the panel returns to a normal condition without requiring a full system reset. Alarm events are latching so that if an alarm occurs, the signals can’t be silenced, even if the smoke detector is taken off the ceiling, until someone with a key to the main panel (an authorized person) investigates.


  3. See my above answer about loop controllers - On modular panels (for large buildings with lots and lots of initiating devices), there will be multiple loop controllers, each driving an SLC of 99-250 devices (manufacturer and protocol dependent).


  4. I can’t answer specifically for C-Tec but I am positive there are wiring diagrams available for this device. Typically a fire panel’s relays (be it supervisory, alarm, or trouble) have 3 terminals: NO (normally open), NC (normally closed), and COM (common). In a normal condition, COM is connected to NC. When the relay activates, the contacts transfer, and COM is connected to NO instead. The reason for all terminals is you never know what type of device is going to be hooked up to the relay; it could be a supervisory bell that gets hooked up to NO and COM so that it will only sound when a supervisory event happens, or it could be power to electromagnetic door holders, which you wire between NC and COM so that in normal conditions, power flows, but when an alarm occurs, the power is stopped.


  5. Sounder bases have relays attached for reasons listed above - maybe to activate an auxiliary signal (i.e. local horn or strobe in a hotel bedroom), but mostly there for whatever reason the building engineers may need it for.
  6. A pulsed relay means that while it’s active, it’s turning ON and OFF at regular intervals - maybe to pulse horns in a signaling order (i.e. 1 burst if it’s zone 1, 2 bursts if it’s zone 2, etc)
  7. A conventional input zone (IDC) or horn/strobe circuit (NAC) has an EOL resistor connected between positive and negative after the last device in the circuit. Therefore, if the wiring is complete and there are no breaks, power reaches the resistor and it will draw a small amount of current. The panel always looks for this small current draw, and if it stops, the panel assumes a wire has broken somewhere in the line and announces a trouble for that circuit.
  8. Monitored output means it’s supervised for wiring completeness - at the end of the line there is an EOL resistor; so long as the resistor can be detected in the circuit, the panel knows the wiring is intact.
  9. Need an example of “Master Alarm” to know for sure.
  10. Yes - for example, sprinkler waterflow detectors typically have a 60-90 second delay before they cause a general alarm. The idea is that city water pressure can fluctuate throughout the day, causing small amounts of waterflow past the flow switch, but an activated sprinkler head would cause continuous flow. The delay is so that small fluctuations in pressure do not cause multiple nuisance waterflow alarms.
  11. Depends on manufacturer. A plug-in card could be a loop controller, could be an audio controller, dialer, etc.
  12. Where panels are interlinked by their alarm relays, typically an alarm on one will trip an alarm on the other, and vice versa - unless they are in different buildings, in which case it may only cause a trouble or supervisory in the other panel. On networked panels that use digital communication, it depends on how the panels are programmed but typically all panels will respond the same to alarms or troubles. Depends on manufacturer and job site
  13. Depends on panel. Typically the battery connection terminals are marked BATT or similar.
  14. Provide an example of said 2-way device?
  15. In class A wiring, yes, there are 2 wires out and 2 wires in, providing a redundant path of communication in the event a wire breaks along the line. In class B wiring, there are only 2 wires out. Most panels support circuits being wired in either style.

Thank you :slight_smile: