Problem: I need to test the emergency shutdown valves at my plant, but don’t want to disrupt our processes by having to close the valves.
Solution: The HIM can verify that a valve is operational without having to follow the standard procedure of completely closing the valve. A logic solver such as a DCS or PLC can send a 90 percent signal to the valve, with the HIM serving as an alarm trip when the valve reaches 90 percent. A second HIM relay trip set to 100 percent verifies that the valve reopened after the test. Because the valve was only momentarily closed and immediately reopened, the process flow is relatively unimpeded and process disruption is kept to a minimum.
Model Number Example
HIM / HART / 2AO / 24DC / -2PRG [DIN]
