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1SVR740120R3300 ABB CT-ARS.21P True OFF-Delay Timer Relay 2C/O

1SVR740120R3300 ABB CT-ARS.21P True OFF-Delay Timer Relay 2C/O

ABB CT-ARS.21P electronic true OFF-delay timer relay with 10 selectable time ranges from 0.05 s to 300 h, 2 c/o relay contacts and 24–240 V AC/DC control supply.

SKU: 1SVR740120R3300Alt SKU: CT-ARS.21PMPN: 1SVR740120R3300
Price
List Price £155.66 ex VAT
Your Price (ex VAT)
£155.66
Manufacturer Lead Time Estimated Delivery 5 weeks
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Manufacturer Lead Time

£155.66

Why Choose the ABB CT-ARS.21P True OFF-Delay Timer?

The ABB CT-ARS.21P is a reliable electronic true OFF-delay timer relay designed for precise time-delayed switching in industrial automation, control panels and electrical control systems. As part of the proven ABB CT-S timer range, it provides a true OFF-delay function without requiring an auxiliary voltage, with two changeover relay outputs for flexible control applications.

The CT-ARS.21P provides 10 selectable time ranges from 0.05 s to 300 h, allowing accurate timing control across a wide range of industrial applications. The timer operates from a wide 24–240 V AC/DC control supply and provides 2 c/o (SPDT) relay contacts rated at 250 V / 4 A.

Featuring Easy Connect push-in terminals, front-face adjustment and a compact 22.5 mm DIN-rail housing, the CT-ARS.21P is designed for straightforward installation within industrial control cabinets. Its true OFF-delay operation allows the outputs to remain energised for the selected time after the control voltage is removed.

Key Advantages

  • Reliable true OFF-delay timer relay for industrial automation.
  • True delay-on-break operation without auxiliary voltage.
  • 10 selectable time ranges from 0.05 s to 300 h.
  • Wide 24–240 V AC/DC control supply.
  • 2 c/o (SPDT) relay contacts for flexible switching.
  • Maintenance-free Easy Connect push-in terminals simplify installation.
  • Compact 22.5 mm wide DIN-rail housing for control cabinets.

Key Features

  • ABB CT-ARS.21P true OFF-delay timer relay.
  • True OFF-delay function without auxiliary voltage.
  • 10 selectable time ranges.
  • 0.05 s to 300 h timing range.
  • 24–240 V AC/DC rated control supply.
  • 2 c/o (SPDT) relay contacts.
  • Relay contacts rated at 250 V / 4 A.
  • Easy Connect push-in terminals.
  • Precise timing adjustment using front-face operating controls.
  • Compact 22.5 mm wide housing.
  • LED status indication.
  • DIN-rail mounting for control panel installation.

Reliable True OFF-Delay Control for Industrial Automation

True OFF-delay timer relays such as the ABB CT-ARS.21P provide controlled switching after the control voltage is removed. This makes the timer particularly useful where equipment, motors, fans, lighting circuits or other loads need to remain energised for a defined period before switching off.

The CT-ARS.21P combines true OFF-delay operation with ten selectable time ranges and a wide 24–240 V AC/DC control supply. Its two changeover relay outputs provide flexible switching within automation and control circuits, while the compact DIN-rail housing and push-in terminals support efficient panel installation.

Typical Applications

  • Industrial automation and control panels.
  • Delayed shutdown and run-on circuits.
  • Motor and actuator control systems.
  • Fan and ventilation run-on applications.
  • Machine control and production equipment.
  • Lighting and electrical control systems.
  • Sequencing and interlocking applications.
  • OEM machinery and industrial automation equipment.

Technical Specifications

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Mounting Type DIN rail
Device Type Single-function timer
Timing Function Off-delay
Switching Current (A) 4 A
Series CT-S Time Relays
ABB order code 1SVR740120R3300
Product type Electronic true OFF-delay timer relay
Product group 310926-Timer Relays
Timing function True OFF-delay / delay on break
Time ranges 10
Time range 0.05 s to 300 h
Rated control supply voltage 24–240 V AC/DC
Output 2 c/o (SPDT) contacts
Contact rating 250 V / 4 A
Auxiliary voltage Not required for true OFF-delay operation
Terminal type Easy Connect push-in terminals
Mounting type DIN rail mounting
Product width 22.5 mm
Product height 85.6 mm
Product depth 103.7 mm
Product net weight 0.115 kg
Operating temperature -25 to +60 °C
Storage temperature -40 to +85 °C
Protection rating Housing IP50 / terminals IP20
Rated insulation voltage 500 V input/output

Frequently Asked Questions

What is the ABB CT-ARS.21P used for?

The CT-ARS.21P is an electronic true OFF-delay timer relay used to provide controlled time-delayed switching after the control voltage is removed in industrial automation and electrical control systems.

What timing range does the CT-ARS.21P provide?

The timer provides 10 selectable time ranges from 0.05 s to 300 h.

What supply voltage does the CT-ARS.21P require?

The CT-ARS.21P operates from a rated control supply of 24–240 V AC/DC.

How many relay outputs does the CT-ARS.21P have?

The timer has 2 c/o (SPDT) relay contacts, providing flexible changeover switching for electrical control circuits.

How is the CT-ARS.21P installed?

The CT-ARS.21P is designed for DIN-rail mounting and uses Easy Connect push-in terminals for straightforward tool-free electrical installation.

Trusted by Automation Engineers Worldwide

ABB CT-S timer relays are used in industrial automation and control applications where dependable, configurable timing and flexible relay switching are required.

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