Industrial TDB120AL Time Delay Relay

The Littelfuse/SSAC TDB120AL is a 120 V AC time-delay relay with a single Form C (SPDT) output, designed for industrial control panels that require a precise, repeatable delay before a load changes state. Timing is DIP-switch selectable across multiple ranges, providing 1 to 1023 seconds of delay in 1-second steps, making it suitable for sequencing, interlocking, and startup delay tasks. The device is a socketable octal plug-in relay and supports a maximum load of 10 A at 120/240 VAC on its SPDT contacts, with an input coil rated for 120 VAC. As part of the TDB series, it implements a delay-on-break type timing function commonly used to control auxiliary relays, alarms, or motor-start sequences in automation and process-control applications. Ideal applications include equipment interlocks, debouncing input signals in control panels, and timed control sequences in HVAC, conveyors, and machine automation where a defined off-delay or timed reset is required.