Allen-Bradley 849-ZAB33 Pneumatic Timing Relay

Allen-Bradley 849-ZAB33 Pneumatic Timing Relay is a legacy Allen‑Bradley timing device that delivers controlled time delays in industrial control circuits using a pneumatic bellows mechanism. Belonging to the 849 family, it functions as a timing relay with a pneumatic timing element driven by compressed air, avoiding electronic timing components in the timing loop; the 849 suite uses synthetic rubber bellows to set and reset timing actions. The ZAB33 designation identifies a specific variant in the catalog, part of a family that includes several enclosure/variant endings (32 and 33 being common suffixes). This model is widely listed as discontinued by major distributors, so available stock is typically limited to surplus or secondary-market sources. Applications include sequencing, interlocks, and safety routines in manufacturing lines where a purely pneumatic timing solution is preferred for reliability or isolation from electrical noise, and it typically partners with standard relays and contactors to implement time-based control without electronics in the timing path.