Applies To:
  • CitectSCADA x.x

I am having trouble setting up communications with the GE SR 750 Data Logger. 

The SR750 uses COMX and the MODBUS protocol. The Data Loggers' address and communications parameters can be found by interrogating the unit using the front panel controls , however this is difficult to drive and an easier method is to use an interface program available from The RS232 cable must be straight through no crossover.

The citect.ini file must include the line [MODBUS]InitType = 3 (Mandatory for communications).

When setting up your tags the tag type must be INT within the range 30001 to 49999 and the tag reference in the manual (SR750/760 Feeder management relay Instruction manual P/N 1601-0044-A9) must be converted to decimal and add 1. 

Input Registers 30001 to 39999 INT / LONG / STRING / REAL
Output Registers 40001 to 49999 INT / LONG / STRING / REAL


Variable Tag Name Last_Trip_Phase_A_current
Data Type INT
Address 30742             (converted to decimal + 1)
Comment Read only register address 02E5 (From the manual)