Triconex TMR Digital Input Module 2

Models 3502E, 3503E, and 3505E can perform a self-test to detect a “stuck-open” condition

in which the circuitry is unable to determine whether a point has entered a shutdown state.

The ability to detect the point of shutdown is an important feature

since most security systems have a power failure trip feature.

In order to detect the presence of a “stuck-open” input,

the switch within the input circuit needs to be turned off in order for the opto-isolated circuit to read a zero input (“off”).

The I/O communications processor will freeze the last reading while the test is running.

All TMR digital input modules support the hot standby feature and require a separate

external termination panel (ETP) with cable connections to the Tricon backplane.

Each module is mechanically keyed to prevent improper installation in the configured chassis.