The MSI switchgear family from Leuze electronic has been completely redesigned and equipped with plug-in terminal blocks. With these interchangeable plug-in modules, the user can decide for himself whether he prefers screw terminals or spring-cage terminals as connection technology. The switching devices function as monitoring and integration modules for safety switches, emergency stop command devices, two-hand control elements, safety light curtains as well as single and multiple light beam safety devices. They also enable the start/restart interlock and contactor monitoring functions. The 'MSI 100' and 'MSI 200' safety controllers as programmable safety switching devices are also suitable for monitoring the safety circuit on small to medium-sized machines.