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1SVR730100R0300 ABB CT-ERS.21S Timer ON-Delay 2C/O
ABB CT-ERS.21S electronic ON-delay time relay with 10 time ranges from 0.05 s to 300 h, 24–240 V AC/DC supply and two changeover relay outputs.
£68.37
Why Choose the ABB CT-ERS.21S ON-Delay Timer?
The ABB CT-ERS.21S is a single-function electronic time relay from the ABB CT-S timer range, designed to provide reliable ON-delay timing for industrial automation and control systems. It provides a straightforward delay-on-make function with two changeover relay outputs for flexible switching applications.
The CT-ERS.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. The adjustable time delay allows equipment, contactors, signalling circuits and other control devices to be switched after a defined period following energisation.
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 designed for DIN rail installation in industrial control panels.
Key Advantages
- Reliable ON-delay electronic time relay for industrial automation.
- Single-function design for straightforward delay-on-make control.
- 10 selectable time ranges from 0.05 s to 300 h.
- Universal 24–240 V AC/DC control supply.
- 2 c/o (SPDT) relay outputs for flexible switching.
- 250 V / 4 A rated relay contacts.
- Compact 22.5 mm wide DIN rail housing.
- Screw connection technology with double-chamber cage terminals.
- Clear front-face adjustment of the selected time range.
- Sealable transparent cover available as an accessory to help prevent unauthorised adjustments.
Key Features
- ABB CT-S timer range.
- ON-delay (delay-on-make) 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.
- 50/60 Hz AC or DC operation.
- Screw connection technology with double-chamber cage connection terminals.
- Front-face screwdriver adjustment for time selection.
- DIN rail mounting for compact control cabinet installation.
- Three LEDs provide operating status indication.
- Sealable transparent cover available as an accessory.
Reliable ON-Delay Timing for Industrial Automation
The ABB CT-ERS.21S provides a dedicated ON-delay function for applications where an output needs to operate after a defined time following energisation. The straightforward single-function design makes it suitable for control circuits where dependable delay-on-make operation is required without the additional complexity of a multifunction timer.
With ten selectable time ranges covering 0.05 s to 300 h, the CT-ERS.21S can accommodate both short machine-control delays and extended process timing requirements. Its two changeover relay outputs provide flexible interfacing with contactors, signalling circuits, motors and other industrial automation equipment.
Typical Applications
- Industrial automation and control panels.
- Motor and contactor control circuits.
- Machine sequencing and timed control.
- Conveyor and production machinery control.
- Delayed switching applications.
- Process automation and equipment sequencing.
- Industrial signalling and alarm circuits.
- Control systems requiring extended time delays.
- Applications requiring universal AC/DC timer operation.
Technical Specifications
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| Contacts | 2 C/O | |
|---|---|---|
| Mounting Type | DIN rail | |
| Device Type | Single-function timer | |
| Timing Function | On-delay | |
| Timing Range | 0.05 s – 300 h | |
| Switching Current (A) | 4 A | |
| Series | CT-S Time Relays | |
| Product type | Electronic time relay | |
| Timer relay type | ON-delay | |
| Timing function | 1 | |
| Time range | 0.05 s–300 h | |
| Number of time ranges | 10 | |
| Control supply voltage | 24–240 V AC/DC | |
| Output | 2 c/o (SPDT) contacts | |
| Rated operational voltage | 250 V | |
| Rated operational current | 4 A | |
| Rated frequency | 50 / 60 Hz / DC | |
| Rated insulation voltage | 500 V input/output, 300 V between output circuits | |
| Rated impulse withstand voltage | 4 kV input circuit, 4 kV output circuits | |
| Minimum switching capacity | 12 V / 10 mA | |
| Protection rating | IP50 housing / IP20 terminals | |
| Operating temperature | -40–+60 °C | |
| Storage temperature | -40–+85 °C | |
| Mounting type | DIN rail mounting | |
| Terminal type | Screw terminals, double-chamber cage connection | |
| Housing width | 22.5 mm | |
| Dimensions (W × H × D) | 22.5 × 85.6 × 103.7 mm | |
| Net weight | 0.13 kg |
Frequently Asked Questions
What is the ABB CT-ERS.21S used for?
The CT-ERS.21S is an electronic ON-delay time relay used to switch control circuits after a defined delay following energisation in industrial automation and control systems.
What timing function does the CT-ERS.21S provide?
The CT-ERS.21S provides a single ON-delay (delay-on-make) timing function.
What time range does the CT-ERS.21S provide?
The CT-ERS.21S provides 10 selectable time ranges covering 0.05 s to 300 h.
What control supply voltage does the CT-ERS.21S require?
The CT-ERS.21S operates from a universal rated control supply of 24–240 V AC/DC.
How many outputs does the CT-ERS.21S have?
The CT-ERS.21S has two changeover (2 c/o) SPDT relay contacts, rated at 250 V / 4 A.
Trusted by Automation Engineers Worldwide
ABB CT-S ON-delay time relays provide dependable timed switching for industrial automation systems where precise delay-on-make control and flexible relay outputs are required within a compact DIN rail device.
