The Safety Relay provides an easy way to enhance security of the doors controlled by the H4 Video Intercom (H4VI) by using a relay module to pulse open the electric lock on a command from an ACC operator.
Installed on the secure side of the door, in the event of tamper attempt with the H4VI, the relay will keep the door securely locked. After tampering is detected, the clear button on the Safety Relay must be manually pressed to restore normal operation.