Cooper Instruments & Systems DFI 250X Digital Weight Indicator - Manual (Page 8)

CF 146 6 V- Rev. 1.0 - 003R-620-100
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This configuration allows for the direct connection of the instrument outputs to most types of PLC.
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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 the outputs are active the PLC will see a 24V signal.
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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.
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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.
Outputs to Drive Relay
Outputs to Drive PLC
6.5 Connecting Shields
To obtain full EMC or for RFI immunity, cable shields MUST be connected to the earth lug on the rear of the
instrument.
This figure shows the connecting cables restrained using cable ties fastened around the cable strain relief anchors.