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ABB CR-U 21 Diode Protection Module
£1.40
Why Choose the ABB 1SVR405661R0000 CR-U 21 Pluggable Module?
The ABB 1SVR405661R0000 is a reliable CR-U 21 pluggable function module designed for ABB CR-U universal relay sockets. This compact relay accessory provides reverse polarity protection and an integrated free-wheeling diode function, helping protect relay coils and improve the reliability of industrial control circuits.
As part of the ABB CR-U interface relay accessory range, the module enables quick plug-in installation and simplified maintenance for relay-based automation systems. It is engineered for applications requiring dependable DC coil protection and efficient control panel integration.
With a rated control supply voltage range of 6–220 V DC, the ABB CR-U 21 module is suitable for industrial automation panels, PLC interfaces, machine control systems and electrical cabinets where reverse polarity protection and coil suppression are required.
Key Advantages
- Compact pluggable function module for ABB CR-U relay sockets.
- Provides integrated reverse polarity protection.
- Includes free-wheeling diode suppression for relay coil protection.
- 6–220 V DC control supply compatibility.
- Quick plug-in installation reduces wiring effort and maintenance time.
- Reliable ABB accessory designed for industrial relay applications.
Key Features
- ABB CR-U 21 pluggable function module.
- Compatible with ABB CR-U universal relay sockets.
- Reverse polarity protection function.
- Integrated free-wheeling diode.
- 6–220 V DC rated control supply voltage.
- Compact plug-in design for relay accessories.
- No output signal function required.
- Suitable for industrial automation and control systems.
Reliable Relay Coil Protection for Industrial Systems
The ABB 1SVR405661R0000 improves relay reliability by protecting DC relay coils against incorrect polarity connection and suppressing voltage spikes generated during coil de-energisation. This reduces electrical stress and supports stable operation in industrial control environments.
ABB CR-U pluggable modules are designed for engineers requiring flexible relay solutions with simple installation and reliable performance. Their modular construction allows efficient integration into automation panels and electrical control systems.
Typical Applications
- Industrial automation control panels.
- PLC interface relay systems.
- Machine building and OEM equipment.
- Electrical control cabinets.
- DC relay switching applications.
- Industrial process control systems.
Technical Specifications
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| Device Type | Accessory | |
|---|---|---|
| Mounting Type | Plug-in socket | |
| Coil / Supply Voltage | 110 V DC, 12 V DC, 125 V DC, 220 V DC, 24 V DC, 48 V DC, 60 V DC, 72 V DC | |
| Manufacturer | ABB | |
| Product type | Pluggable function module | |
| Series | CR-U | |
| Model | CR-U 21 | |
| Order code | 1SVR405661R0000 | |
| Function | Reverse polarity protection and free-wheeling diode | |
| Control supply voltage | 6–220 V DC | |
| Compatible relay range | ABB CR-U sockets | |
| Output signal | None | |
| Mounting type | Plug-in mounting | |
| Dimensions (H × W × D) | approx. 24 × 34 × 9 mm | |
| Weight | approx. 0.007 kg | |
| EAN | 4013614529023 | |
| HS Code | 85411000 | |
| Country of Manufacture | China |
Frequently Asked Questions
What is the ABB 1SVR405661R0000 used for?
The ABB 1SVR405661R0000 is a CR-U 21 pluggable module used with ABB CR-U relay sockets to provide reverse polarity protection and free-wheeling diode suppression.
Which relay sockets are compatible with this module?
This module is designed for use with ABB CR-U universal relay sockets.
What voltage range does the CR-U 21 support?
The module supports a rated control supply voltage range of 6–220 V DC.
What protection functions are included?
The module provides reverse polarity protection and an integrated free-wheeling diode for relay coil protection.
Where is the ABB 1SVR405661R0000 installed?
The module is typically installed on ABB CR-U relay sockets inside industrial control panels and automation systems.
Trusted by Automation Engineers Worldwide
ABB CR-U pluggable relay accessories provide reliable protection, flexibility and efficient integration for industrial automation systems, helping engineers build dependable control solutions.
