Simplex 565-654 — service replacement electronics for the relay versions of the Simplex 4098 TrueAlarm duct sensor housings.
Simplex catalogs this part as 4098-9751, 9753 Sensor W/Relay. It is the relay-equipped assembly carried inside those two duct housings, not a smoke sensor head — the sensing element is the separately ordered 4098-9714 photoelectric sensor. It is what a technician orders when a housing's relay or communications section fails but the housing, sampling tube and field wiring are sound.
- Host housings: 4098-9751 in-duct and 4098-9753 sampling tube
- Host housing communications: IDNet or MAPNET II, one address per housing
- Host housing relay: single Form C, 1 A @ 28 VDC power limited; 1/2 A @ 120 VAC non-power limited
- Host housing relay power: 18 to 32 VDC, four wire, from the fire alarm system
Check the housing model and the number printed on the assembly you remove before ordering; Simplex lists more than one 4098 duct sensor board and they are not interchangeable.
