Simplex 565-653 — a Simplex 565-series printed circuit board assembly (PCA) for 4098 TrueAlarm duct sensor housings.
PCA means printed circuit assembly: this is a board, not a sensing head, so it does not replace a detector. The duct attribution comes from distributor price-book listings, not a published Simplex document, and no parts list reviewed here names 565-653. Match the number printed on the board being replaced.
- Simplex 565- numbers are grouped under BOARDS in the 4020 parts list 574-756 Rev. A
- Adjacent numbers are panel network hardware: 565-649 Network Interface Card, 565-650 Physical Bridge Board
- In the 4098 duct family the sensing head is separate: the 4098-9714 TrueAlarm sensor
- 4098-9755 is the duct sensor housing with no relay output, powered from IDNet or MAPNET II
- 4098-9756 adds a supervised output for remote relays, needs separate 24 VDC, includes one relay
Simplex duct electronics split by function rather than into one board: the earlier CDT parts list separated an interface board (565-124 with relay, 565-143 without) from a base board (565-131, or 565-144 without). Match 565-653 to the board already fitted.
