Learn about Magnetic Interlock Switches and what the difference is between a regular magnetic interlock and a coded one.
Magnetic interlock switches are more like proximity sensors – but they detect when a magnet comes near the sensor. The beauty of these is they don’t require physical contact like a regular switch so they are going to be a lot more reliable. There are two kinds of these – one just uses a magnet to pull a reed switch closed and doesn’t require any power. The other one- called a “coded Interlock switch” – does require power, and even has an LED to show when the switch is activated. With this one, instead of a single magnet, it has a several magnets in it with alternating polarities. The sensor actually verifies those polarities before activating the switch. That means someone can’t walk up with any old magnet and fake out the sensor. For example if I take this regular magnet and place it here, nothing happens. But if I use this coded magnet, now the light turns on. You can actually see the magnetic fields if I hold this magnetic paper up to it. Looks like this one has three magnets in it. Interlock switches are available in a variety of package styles, light medium and heavy duty, sizes and orientations. You may want to get one with a larger surface area so you don’t have to worry about perfect alignment for example. If you have any questions, please contact AutomationDirect’s free award winning tech support during regular business hours. They will be happy to help. And don’t forget the forums. There are lots of folks there that love to share their years of experience. Just don’t post and questions intended for AutomationDirect’s support team there, they don’t monitor the forums on a regular basis.