Eaton's Wiring Devices Technical Support Locking Devices. What is the NEMA configuration used for the Eaton 50 amp locking devices? Is your model WD7761 rated 600V AC? What is the cord range diameters for 50A locking devices? What testing and code standards do the Eaton 50 Amp locking devices meet? What material is used for the 50 amp locking devices?