Fire-Lite REL-4.7K-BP — 4.7 kΩ end-of-line resistor with leads, the bulk-pack ordering code in the Honeywell REL end-of-line resistor family.
A Class B fire alarm circuit is supervised by passing a small current through a resistor at the far end of the run. Cut the wire and the current stops, short it and it rises, so the panel can tell an open from a short and both from a healthy circuit.
- Resistance 4.7 kΩ; Honeywell states the REL resistors come in 4.7 or 47K ohm
- Honeywell states these resistors are sold in packs of ten
- Terminates Style B, Class B initiating device circuits
- Terminates Style Y, Class B notification appliance circuits too
- Those initiating circuits run at a nominal 20 VDC, 100 ohms maximum loop resistance
- Those circuits are supervised and power-limited, so unused ones are terminated too
The 47 kΩ member of the family is REL-47K and the two cannot be swapped. Fire-Lite panel manuals separately call out part 71252 for the same duty, a 4.7 kΩ half-watt resistor; that is a different catalogue number, and no document read states a wattage or tolerance for REL-4.7K.
