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1SBN040100R1011 ABB WA4-11 Mechanical Interlock Auxiliary Contact Accessory 1NO 1NC
ABB WA4-11 is a 24–60 V AC/DC mechanical latching unit providing electrical impulse or manual release for compatible AF09–AF65 contactors and NF one-stack contactor relays.
£36.62
Why Choose the ABB WA4-11 Mechanical Latching Unit?
The ABB WA4-11, order code 1SBN040100R1011, is a compact mechanical latching unit designed for compatible ABB AF contactors and NF contactor relays. It mechanically holds the associated contactor or relay in its closed position if the supply voltage is interrupted or fails.
The WA4-11 converts a standard contactor into a compact latched contactor without requiring continuous coil energisation to maintain its switched state. The device can be unlatched electrically using an AC or DC control impulse or manually using the pushbutton on its front face.
With a rated control circuit voltage of 24–60 V AC/DC, the WA4-11 is suitable for compatible AF09 to AF65 contactors and NF one-stack contactor relays. It clips directly onto the front of the host device and occupies the two central accessory slots.
Key Advantages
- Converts compatible contactors into compact mechanically latched contactors.
- Maintains the closed state if the contactor coil supply fails.
- 24–60 V AC/DC unlatching coil supports common control supplies.
- Provides both electrical impulse and manual unlatching.
- Front-clipping installation simplifies assembly and maintenance.
- Allows CA4 auxiliary contact blocks to be fitted in the remaining front slots.
Key Features
- ABB WA4 mechanical latching unit series.
- Compatible with ABB AF09–AF65 contactors.
- Compatible with ABB NF one-stack contactor relays.
- 24–60 V AC at 50/60 Hz control voltage.
- 24–60 V DC control voltage.
- Maximum electrical impulse duration of 4 s.
- Minimum electrical unlatching impulse of 50 ms.
- IP20 degree of protection.
Reliable Mechanical Latching for Control Systems
Mechanical latching allows a contactor or contactor relay to remain closed without continuous energisation of its operating coil. This is useful where the switching state must be retained during a loss of control voltage or where reducing continuous coil power consumption is desirable.
The ABB WA4-11 mounts on the front of the compatible device and uses an electromagnetic impulse for electrical release. Its unlatching coil is intended for short control impulses and must not be permanently energised, while the integrated front pushbutton provides a convenient manual release method.
Typical Applications
- Latched motor-control contactor assemblies.
- Industrial machinery control panels.
- Power distribution and load-switching circuits.
- Control systems requiring state retention during voltage loss.
- Energy-conscious contactor installations.
- Automation systems using ABB AF contactors or NF contactor relays.
Technical Specifications
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| Terminal Type | Screw | |
|---|---|---|
| Device Type | Accessory | |
| Manufacturer | ABB | |
| Series | WA4 | |
| Model | WA4-11 | |
| Order code | 1SBN040100R1011 | |
| Product type | Mechanical latching unit | |
| Compatible contactors | AF09–AF65 | |
| Compatible contactor relays | NF one-stack | |
| Rated control circuit voltage | 24–60 V AC/DC | |
| AC control frequency | 50 / 60 Hz | |
| Rated insulation voltage | 690 V AC | |
| Maximum electrical impulse time | 4 s | |
| Minimum latching impulse time | 120 ms | |
| Minimum unlatching impulse time | 50 ms | |
| Unlatching time for NO contact opening | 8–15 ms | |
| Unlatching time for NC contact closing | 10–17 ms | |
| Operating temperature | −25 to +70 °C | |
| Storage temperature | −60 to +80 °C | |
| Maximum operating altitude | 3000 m | |
| Maximum switching frequency | 600 cycles/h | |
| Protection rating | IP20 | |
| Terminal type | M3.5 screw terminals | |
| Terminal tightening torque | 1.2 Nm | |
| Dimensions | 60 × 41 × 10 mm | |
| Weight | 0.08 kg | |
| Standard | IEC 60947-4-1 |
Frequently Asked Questions
What is the ABB WA4-11 used for?
The WA4-11 mechanically holds a compatible ABB contactor or contactor relay in its closed position, including when voltage at the contactor coil terminals is lost.
Which contactors are compatible with the WA4-11?
The unit is designed for ABB AF09–AF65 contactors and NF one-stack contactor relays.
What control voltage does the WA4-11 require?
The unlatching coil operates from a rated 24–60 V AC/DC supply, with AC operation at 50/60 Hz.
Can the ABB WA4-11 be released manually?
Yes. The latching mechanism can be released manually using the pushbutton on the front of the WA4-11 or electrically using a short AC or DC impulse.
Can the WA4-11 coil remain continuously energised?
No. The electromagnetic unlatching coil is designed for impulse operation and must not be permanently energised; the maximum electrical impulse time is 4 s.
Trusted ABB Contactor Control
ABB WA4 mechanical latching units provide dependable state retention, compact front-mounted installation and flexible electrical or manual release for compatible AF contactors and NF contactor relays.
