Allen-Bradley 849-ZOD324 Pneumatic Timing Relay

Allen-Bradley 849-ZOD324 Pneumatic Timing Relay is a Bulletin 849 timing relay that provides an adjustable on-delay in industrial control circuits. It is a pneumatic timing device that uses a synthetic rubber bellows and a screw-type needle valve to meter the air flow, delivering a maintained-contact output after the preset interval. The coil operates at 110/120 VAC, 50/60 Hz, aligning with common North American control panels, and the timing action is pneumatic rather than electronic. This model belongs to the 849 family, with historical open-type and enclosure variants such as 849-ZOD32 (open type) and 849-ZAD32 (Type 1 enclosure), and the 849-ZOD324 sits within that lineage. The timing is set pneumatically and resets when supply is removed, offering a simple, rugged means to introduce delays without relying on electronic timers. The output closure provides a maintained contact suitable for energizing other loads or relays, enabling sequencing, interlocks, start/stop delays, or other control logic in machines and processes where a defined interval between input and control action is required.