Allen-Bradley 700-NT400A1 Pneumatic Time Delay Relay

Allen-Bradley 700-NT400A1 is a pneumatic time-delay relay that combines a Bulletin 700-N400A1 industrial control relay (4 normally open contacts) with a Bulletin 700-NT pneumatic timing unit for AC on-delay timing. The pneumatic timing module provides the delay after energization and includes a 1 normally open and 1 normally closed contact within the timing unit to support sequencing logic, designed to mount on a 700-N relay base for compact control assemblies. This configuration supports AC operation, with coil voltage variants for the 700-N400A1 listed as 110V 50/60 Hz and 120V 60 Hz. Typical applications include coordinating start-up sequences for solenoids, valves, and actuators in control panels where a controlled delay between energization and load activation is required. The 700-NT family is documented by Rockwell Automation as ON-delay pneumatic timing units suitable for mounting on 700-N series relays, making the 700-NT400A1 a compact, integrated delay solution well-suited to industrial automation tasks that demand precise timing in relay‑controlled circuits.