Issue
Why does my DM point on an MR always go into alarm?
Environment
I/NET site
Cause
Why does my DM point on an MR always go into alarm?
Resolution
The time to state timer in the DM/DC point resides up in the SLI. If an MR-DDC module starts the DC point, the MCI has no mechanism to start that timer. Therefore, the DM will create an alarm with every change of state. If the DC is controlled by an event sequence or point extension, the DM functions properly. If you need to use DDC, use a DO and DI and create a DA for the alarm handling. Attach a calculation (module or extension) to the DA of P0=P1 to compare the DO and DI points. Give the DA an alarm delay equal to the value you would have used for the time to state setting.
