The new interface module PDP20 F 4 mag from Pilz can be used for series connection of safety switches, such as tongue interlocks or magnetic safety switches, up to PL e. As such, it provides a standard-compliant solution in accordance with EN ISO 13849-1. The interface module can be connected to dual-channel evaluation devices (such as the popular PNOZ safety relays, PNOZmulti configurable safety relays, PSS safety PLCs). Up to 4 switches can be connected to each module. PDP20 interface modules also offer a high level of decentralisation due to the ability to cascade modules. Each module features 4 dual-channel inputs and 2 solid-state safe outputs (OSSDs), 1 diagnostic solid state output and 2 test pulsed outputs. To cascade multiple modules, the OSSDs of one are fed into one of one of the dual-channel inputs of the next module. The interface modules makes a compact solution for series connections, which ultimately find their way back to a final safety relay or other safety controller. Where users require the functionality of 'nesting' safety guard inputs (including light curtains, RFID coded switches, standard interlocks, E-stops, resets etc.) without the availability of localised cabinets to house PDP20 modules, the supplier already offers an IP67-rated system PDP67 F 4 Code and PDP 67 F 8DI ION.