The Allen-Bradley 849A-ZOC24 Pneumatic Timing Relay is an Allen-Bradley/Rockwell Automation 849 series pneumatic timing relay that allows a user-configurable time period to be set in which it will activate the electrical contacts in a system. The minimum on-delay time rating of this pneumatic timing relay is 0.05 seconds and its maximum on-delay time can be configured at up to 180 seconds. The time delay is achieved by using a pneumatic damping system that is designed to delay the activation of the relay contacts for a user-defined amount of time. The Allen-Bradley 849-ZAB32 Pneumatic Timing Relay is able to withstand a continuous carrying current between its contacts of up to 10 Amps. Its recommended operating temperature range is from 0 to 104 degrees Fahrenheit (-17.7 to 40 degrees Celsius), if there is no water or condensation in the environment that could come into contact with the bellows mechanism inside the timer.

The Allen-Bradley 849 series 849A-ZOC24 Pneumatic Timing Relay offers the final users a way to provide a user-configurable time delay by electro-pneumatic means for applications with high levels of electrical interferences and applications in hazardous environments which may not be appropriate for electronic timing relays. The pneumatic operating mechanism of the Allen-Bradley 849A-ZOC24 Pneumatic Timing Relay makes it immune to external electric disturbances or interferences, and thus an ideal solution in places where a high level of atmospheric contamination or interference is expected. The timing relay comes from the factory as a normally open switch that needs an external control signal to energize its coil and to be able to close the electrical circuits that are connected to its terminals. Only properly trained technicians who are proficient in the maintenance of pneumatic systems should be assigned for the maintenance or repair of this timing relay.