Model HTRI-S can only monitor and report the status of the contact, while Model HTRI-R incorporate
The Model HTRI-D is a dual-input module that is designed to supervise and monitor two (2) sets of dry contacts. Model HTRI-D only requires one (1) address, but responds independently to each input. Model HTRI-D is ideal for monitoring a water-flow switch and its respective valve tamper switch. Model HTRI-D flashes twice ─ once for each address, and Model HTRI-R LED indicates a change of state in the relay. The device’s microcomputer chip has the capacity of storing, in memory, identification information; as well as important operating-status data.