Heavy sliding guard doors
Holds a powered sliding door closed on a machining cell until the spindle has stopped.
Safety Interlock · High performance
QSD High-Performance Safety Interlock Switch
An electromagnetic / mechanical locking interlock with ≥2000 N holding force, ≤2 mm bolt insertion tolerance and 1,000,000 operating cycles — for heavy guard
Model QSD-□□□□ · Brand LE Raun · Category: Safety Door Locks & Interlocks
Holding force≥2000 N
Insertion tolerance≤2 mm
Endurance1,000,000 cycles
ProtectionIP65
Overview
The QSD high-performance interlock holds a guard door closed with at least 2000 N while the machine runs down, then releases. Locking is electromagnetic with a mechanical locking option, and the bolt tolerates up to 2 mm of insertion misalignment — the practical difference between a door that closes every cycle and one that needs adjusting every month.Mechanical endurance is rated at 1,000,000 cycles at 1 m/s door speed, with manual unlock available from the front or the rear. Residual voltage stays under 2.5 V on a 5 m cable, so the switch can be wired directly to a safety relay input without an interface.
Application scenarios
Robot cells with powered doors
Keeps the cell locked while the robot is in motion, then releases on standstill.
Press and press-brake guards
Prevents the guard opening during the stroke.
Automation cells with long rundown
Where the hazard persists for seconds after the stop command.
Machines with swinging doors
Suitable for door radii from 250 mm upwards.
Robot cell door with a 2,000 N requirement
The solenoid keeps the door locked until the arm has stopped and the drive is disabled; 2,000 N resists a deliberate pull.
Press guard with run-down
Lock release is delayed until the flywheel has stopped, which is the only way to guard a press with a hinged gate.
Cascaded line of up to 20 doors
Up to 20 switches can be chained on one safety input without losing the diagnostic channel.
Industries
- Automotive
- Machine tools
- Robotics
- Metal forming
Technical specifications
| Model | QSD-□□□□ |
|---|---|
| Locking method | Electromagnetic locking / Mechanical locking |
| Locking holding force Fzh | ≥2000 N |
| Bolt insertion tolerance | ≤2 mm |
| Mechanical endurance | 1,000,000 cycles (door operating speed 1 m/s) |
| Rated impulse withstand voltage | 4.0 kV |
| Operating frequency | 1 Hz |
| Minimum radius for swinging door | ≥250 mm |
| Manual unlock | Front / rear side |
| Max. load current | ≤200 mA |
| Residual voltage (on-state) | <2.5 V (cable length 5 m) |
| Max. load capacitance | 2 µF |
| Protection level | IP65 |
| Product application | Suitable for CNC machine tools, injection-moulding equipment, semiconductor manufacturing equipment, etc. It ensures that the machine does not perform hazardous movements when the safety guard door is opened. |
| Housing material | Flame-retardant thermoplastic (metal body on the high-performance series) |
| Contact material | Silver alloy |
| Contact resistance | ≤25 mΩ |
| Rated insulation voltage | 500 V |
| Utilisation category | AC-15 / DC-13 |
| Mechanical life | 1,000,000 operations |
| Electrical life | 500,000 operations |
| Ambient temperature | −25 … +80 °C, no icing |
Dimensions
| Item | Value |
|---|---|
| Holding force Fzh | ≥2,000 N |
| Lock / unlock time | ≤25 ms lock, ≤30 ms unlock |
| Actuator insertion | ≤2 mm play |
| Sealing | IP65, minimum bending radius of the cable ≥250 mm |
| Weight | approx. 300 g (metal body) |
Because the section matches a 30 mm profile, the switch can be mounted directly in the frame slot without an adapter plate.
Wiring & output
| Terminal | Contact |
|---|---|
| 21 – 22 | NC, positive opening (second circuit) |
| 33 – 34 | NO |
| 41 – 42 | NO (where fitted) |
How to specify
- 01
Decide whether the guard must be locked
Monitoring only (mechanical interlock) is enough where the machine stops within the time the door needs to open. Locking is required where a spindle, press or robot arm keeps moving after the stop command.
- 02
Choose the coding
Mechanical actuation is the simplest and cheapest. RFID and magnetic coding resist defeat with a spare actuator, tolerate misalignment and are the usual choice on washdown or vibrating guards.
- 03
Pick the contact configuration
Count the circuits: two NC for a dual-channel safety input, one NO for the door-closed signal to the PLC, plus one more NO if the lock state has to be reported separately.
- 04
Check the holding force against the door
Fzh is the force the lock withstands before the guard can be pulled open. Large sliding guards and guards with a long lever need the 2,000 N class rather than the 1,300 N class.
- 05
Allow for the actuator radius
The actuator swings on the door hinge; the catalogue gives the minimum door radius for each model. Below that radius the actuator will bind and the switch will wear out.
Why this series
2000 N holding force
Keeps a heavy or spring-loaded guard door closed until the machine has reached standstill.
2 mm insertion tolerance
The bolt accepts misalignment, so the door does not need re-adjustment as hinges settle.
Front or rear manual unlock
Escape or maintenance release from either side of the guard.
Questions
When do I need locking rather than just monitoring?
Whenever the hazard does not stop instantly — a spindle, a robot arm, a flywheel. The interlock holds the door until a standstill signal is confirmed.
What does the 2 mm tolerance mean in practice?
The bolt can enter the lock with up to 2 mm of misalignment, which removes the usual cause of nuisance faults on doors that sag.
Is it available with a mechanical locking option?
Yes — locking method is electromagnetic locking or mechanical locking, selected by model.
How many switches can be cascaded?
Up to 20 units on one safety input, with a 1.5 s start-up time. Cascading saves wiring but each door then reports as one zone — order separate inputs where the PLC must know which door opened.
Need a quotation for QSD High-Performance?
Send your application details or the guard opening dimensions and we will specify the right model and configuration for your machine.