Why Choose the ABB CT-APS.21S OFF-Delay Timer?
The ABB CT-APS.21S is a single-function electronic time relay from the ABB CT-S timer range, designed to provide reliable OFF-delay timing for industrial automation and electrical control systems. It provides a delay-on-break function, keeping the relay outputs active for a defined period after the control signal is removed.
The CT-APS.21S provides 10 selectable time ranges from 0.05 s to 300 h and operates from a universal 24–240 V AC/DC control supply. Its voltage-related, non-floating control input provides dependable triggering for machinery, control panels and automated processes.
The timer features 2 c/o (SPDT) relay contacts rated at 250 V / 4 A. Its compact 22.5 mm wide housing uses screw connection technology with double-chamber cage terminals and is suitable for DIN rail installation in industrial control cabinets.
Key Advantages
- Reliable OFF-delay electronic time relay for industrial automation.
- Dedicated delay-on-break timing function for straightforward control applications.
- 10 selectable time ranges from 0.05 s to 300 h.
- Universal 24–240 V AC/DC control supply.
- 2 c/o (SPDT) relay contacts for flexible switching.
- 250 V / 4 A rated output contacts.
- Voltage-related, non-floating control input.
- Compact 22.5 mm wide DIN rail housing.
- Screw connection technology with double-chamber cage terminals.
- Sealable transparent cover available as an accessory to help prevent unauthorised adjustments.
Key Features
- ABB CT-S timer range.
- OFF-delay (delay-on-break) timing function.
- 10 selectable time ranges from 0.05 s to 300 h.
- 24–240 V AC/DC rated control supply.
- 2 c/o (SPDT) contacts.
- 250 V / 4 A rated output contacts.
- Voltage-related, non-floating control input.
- 50/60 Hz AC or DC operation.
- Screw connection technology with double-chamber cage connection terminals.
- DIN rail mounting for compact control cabinet installation.
- LED status indication.
- Sealable transparent cover available as an accessory.
Reliable OFF-Delay Timing for Industrial Automation
The ABB CT-APS.21S provides dedicated OFF-delay timing for applications where relay outputs need to remain active for a defined period after the control signal is removed. The straightforward single-function design makes it suitable for control circuits requiring predictable delay-on-break operation.
With ten selectable time ranges covering 0.05 s to 300 h, the CT-APS.21S can accommodate both short machine-control delays and extended process timing requirements. Its two changeover relay contacts provide flexible interfacing with contactors, signalling circuits, machinery and other industrial control equipment.
Typical Applications
- Industrial automation and control panels.
- Motor and contactor control circuits.
- Machine sequencing and timed control.
- Conveyor and production machinery control.
- Delayed switch-off applications.
- Process automation and equipment sequencing.
- Industrial signalling and alarm circuits.
- Cooling and ventilation run-on control.
- Lighting and timed shutdown circuits.
- Control systems requiring extended OFF-delay timing.
