Cooper Instruments & Systems DFI 250X Digital Weight Indicator - Manual (Page 10)

CF 147 6 version 1.1
Figure 8: Remote Input
3.9.3 Outputs
The output drivers for the instrument are isolated open emitter transistor drives that are capable of driving up to a
total of 300mA. This configuration allows for the direct connection of the instrument outputs to most PLC types.
The voltage applied to the COM terminal appears on the output lines (i.e. OUT1 and OUT2) when the outputs are
active (e.g. to connect to a PLC connect +24V to the common terminal). The outputs can then be connected directly
to PLC inputs so when activated the PLC will see the 22V signal (approx. - the exact switch loss will depend on
loading of the output).
To drive external loads (e.g. relays), connect the relay coil positive supply to the output common and the output line
directly to one side of the relay coil. Connect the other end of the relay coil to the negative supply. It is
recommended that fly-back diodes or transient suppressors be fitted across relay coils to limit switching noise.
Figure 9: Instrument Outputs to Drive Relay
Figure 10: Instrument Outputs to Drive PLC
3.10 GSE-LINK (Optional)