To capture the occurrence of momentary digital inputs, such as from push buttons, the digital
input channel is configured as a latched input.
Configuring the channel as latched is accomplished by setting:
l DITYPE to Latched.
When configured as a latched input channel, an input pulse that is on for a minimum of 40
milliseconds is latched true for 1.5 seconds. This ensures that any control function block that
needs to monitor this input executes at least once during the time that the signal is latched on.
When the DITYPE is set latch, the EVTOPT cannot be SOE and vice versa.
10.14.3 Comparing parameters between Series C and PMIO that
support DI
The following parameters are:
l specific to DI and found on various tabs on the DI channel block, and
l work identically to the same named PM I/O counterparts.
DI supported parameters for current Series C I/O
that work identically to the same named PM I/O parameters
DITYPE PVRAW
PV BADPVFL
The following are parameters that support Series C DI and work differently than the same named
PM I/O counterparts.
DI supported parameters for current Series C I/O
that work differently than the same named PM I/O parameters
PVSTS
10.14.4 Open Wire Detection - DI Channel blocks
The open wire diagnostic detects and annunciates broken field wires. In addition, a seemingly valid
PV from a channel diagnosed as having a broken-wire will not be made available (thus preventing
incorrect control action).
