Looking for more safety for your team?
Guard locking safety interlock switches from Bernstein ensure the safe operation of machine guards, doors and gates around high-risk industrial processes. These industrial guard locking devices secure access points until machines are fully stopped and safe to open. The SLC door interlock switch is modular and highly customisable.
Guard locking safety switches are machine safety devices that hold guards and access doors in a locked position until hazardous conditions are cleared. By combining guard monitoring and locking functions, these interlocks prevent premature access and ensure compliance with modern industrial safety standards such as ISO 14119 and ISO 13849-1.
Explore your options below.
SLC Door Interlock Switch
Customisable. Modular. Economical.
If you need to open a door while your machine is switched off—for maintenance work, for example—the SLC has an Allen key-operated auxiliary manual release.
And with four slow-action contacts, you'll always be able to tell;
is the door closed or open? And locked or unlocked?
You can also choose from two different guard locking principles. This dictates behaviour during a power loss:
- Spring-to-lock: must be energised to unlock.
- Power-to-lock: must be de-energised to unlock.
What is Guard Locking?
Guard locking is a safety function that locks a safety guard in the closed position until all hazardous energy is neutralised, preventing machine restart and reducing risk of operator injury. Interlocks with guard locking combine monitoring and locking actions in one device.
Power-to-Lock vs Power-to-Release
Many products support power-to-lock (PTL) or power-to-release (PTR) modes. Power-to-lock requires energising to unlock the guard, while power-to-release requires energising to lock — which affects behaviour during power loss.
Looking to replace or retrofit a door interlock switch?
Our technical team is here to help. Get in touch.
A truly modular switch.
Five head positions. Four actuator options. Plenty of flexibility.
Set the SLC switch up your way.
The modular metal head can rotate 4×90°, or pop off the top cover and actuate from above.
It's built to withstand high mechanical stress.
Choose from four different actuators, all high-quality stainless steel. Each actuator has a different minimum actuating radius.
Don't get stuck outside. Or caught inside.
Optional escape & emergency releases are available.
Set your team up with a clear path to safety—from either side of the door.
Escape release: enables immediate opening from inside the dangerous area in case of an emergency. Sold as a basic set, with extension modules (20 & 40mm) available.
Emergency release: for immediate opening from outside the dangerous area in case of an emergency.
Optional sliding handle actuator.
Everything you need to get started.
The ergonomic handle guarantees that the actuator inserts correctly, every time—even for doors that aren't perfectly aligned.
The variant with escape release (BF1-SLC ES) includes an additional handle to be able to open the door from within the danger area when using the function. This requires at least the basic set (ESCR-B).
Also available: SLK Door Interlock Switch
Plastic-bodied, with guard locking, Bernstein's type SLK door interlock switch is still in use across Australia and the world.
The SLK switch is available in versions with spring force locking action and magnetic force locking action.
If you've got an SLK switch installed and you're looking for a like-for-like replacement, you can pick one up online today.