Guardmaster 440N

The Allen-Bradley Guardmaster 440N family is a line of non-contact safety interlock switches designed for machine guarding applications where physical contact between the actuator and switch body is not required. The family encompasses two primary sub-series found across its 184 catalog numbers: the Sipha (440N-S) series and the SensaGuard (440N-Z) series. In the 440N-Z catalog number, the characters following the prefix encode key configuration details — the Z21 base indicates the SensaGuard platform, the next character denotes coding type (S=standard, U=unique, X=cross-reading), the following digit reflects contact configuration (e.g., 1=2 N.C. safety only, 2=2 N.C. safety + 1 N.O. aux), and the connector suffix identifies the output connection style (H, J, A, B, etc.). Popular in-stock examples include the 440N-Z21S26H (standard-coded, 2 N.C./1 N.O., solid-state) and the 440N-S32013 Sipha control unit operating at 24V AC/DC with automatic/manual reset. For full electrical ratings, dimensional data, and selection guidance, refer to the Guardmaster 440N Safety Switch Technical Data.