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How is the Real Time Clock set in TelePACE?
The real time clock (RTC) is set:
- Manually, by using the Controller | Real Time Clock command,
- Dynamically, by utilizing controller logic (ladder or C/C++) to write to preconfigured RTC registers, and
- Remotely, by TeleBUS (Modbus) protocol messages writing to preconfigured RTC registers.
To manually set the RTC:
- Establish communication with the controller.
- Select the Controller | Real Time Clock command. The following dialog appears:

- To write the displayed PC time to the controller, select the set to PC Time radio button and then the Write button.
- To write a user-entered time to the controller, select the Set to User Entered Time radio button, fill in all RTC entry fields with valid entries and select the Write button.
- To adjust the controller time by seconds, select the Adjust Forward or Backward radio button, enter a positive seconds value to move the clock forward or a negative seconds value to move the clock backwards and select the Write button.
To dynamically set the RTC:
- Establish communication with the controller.
- Add the CNFG Real Time Clock and Alarm module to the controller’s existing register assignment. This module reserves eleven IO database registers for use by the RTC. See the diagram below.

- Add ladder logic functions (PUTU, MOVE etc), or C/C++ code to write valid values to the individual RTC registers as defined by the register assignment module. Refer to the TelePACE User and Reference Manual, (Ladder Logic Register Assignment Reference / Register Assignment Reference / Configuration IO Modules / CNFG Real Time Clock and Alarm section) for individual register assignments. Note: The logic must be programmed to write to the registers on a one-shot basis. Do not write to these registers continually as the RTC will not function properly.
- Write the program, including the register assignment, to the controller.
- Run the code.
To remotely set the RTC:
- Establish communication with the controller.
- Add the CNFG Real Time Clock and Alarm module to the controller’s existing register assignment as previously explained.
- Write the register assignment to the controller.
- Using external devices that support Modbus protocol, write valid values to the individual RTC registers as defined by the register assignment module. Do not write to these registers continually as the RTC will not function properly.