Elevator Recall Relays Wiring

[designer82]

Regarding elevator recall relays...
how does either the Primary or Alternate relay know to trip (and not both at same time) from just the SLC wiring (shown to the right of them)?

 

[designer82]

Is it such that the SLC circuit has both input and output capability?
So if a smoke detector triggers, it doesn't send its signal throughout all SLC devices, it just sends it to Control Panel, then in turn Control Panel sends an output signal just to designated device address? (as in via magic)?

 

[gadfly56]

The panel is going to have functions that assign inputs and outputs. So function F1 for primary recall, will have all the elevator lobby smoke detectors EXCEPT for the primary floor elevator lobby detector, the machine room smoke detectors, and the hoistway smoke detectors, if any, assigned to the input of F1. Usually, they are placed in a zone and the zone becomes the input to the function. The output of the function is assigned to the address of the FRM-1 relay module. Easy peasey.