Applies To:
  • CitectSCADA 3.xx, 4.xx, 5.xx

I am using the Citect SIDirect driver and I am trying to write to a KT data type in my S5 which is a "constant time value" data type. I have defined a Citect variable of type BCD, but get strange values being written my PLC. If I enter a time value greater than 32700 which equates to 327 seconds then I get random values being written to the PLC. 

The S5 series do not support the entry of preset timer values directly into timer variables. Apparently it is supported in the S7 series.

These variables are not double buffered and preset values cannot be entered directly.

The workaround is to write your preset timer value to a word in the S5, and then write some PLC code to copy this value into the Timer Variable, KT. Then use the some PLC code to load this KT value into the timer.