Rockwell Automation 1769-IF4FXOF2F Compact Combination Fast Analog I/O Module - Manual (Page 12)

12 Compact Combination Fast Analog I/O Module
Publication 1769-IN081A-EN-P - February 2007
System Wiring Guidelines
Consider the following when wiring your system:
•
All module commons (ANLG COM) are connected in the analog module.
•
The analog common (ANLG COM) is not connected to earth ground inside
the module.
•
Channels are not isolated from each other.
•
Use Belden 8761, or equivalent, shielded wire.
•
Under normal conditions, the drain wire and shield junction must be
connected to earth ground via a panel or DIN rail mounting screw at the
analog I/O module end. Keep the shield connection to ground as short as
possible.
(1)
•
To ensure optimum accuracy, limit overall cable impedance by keeping your
cable as short as possible. Locate the I/O system as close to your sensors or
actuators as your application will permit. (2)
•
If multiple power supplies are used with analog inputs, the power supply
commons must be connected.
•
The 1769-IF4FXOF2F module does not provide loop power for analog
inputs. Use a power supply that matches the input transmitter specifications.
•
Differential analog inputs are more immune to noise than single-ended
analog inputs.
•
Voltage outputs (Vout 0+ and Vout 1+) of the 1769-IF4FXOF2F module are
referenced to ANLG COM. Load resistance for a voltage output channel must
be equal to or greater than 1K
Ω
.
•
Current outputs (Iout 0+ and Iout 1+) of the 1769-IF4FXOF2F module source
current that returns to ANLG COM. Load resistance for a current output
channel must remain between 0 and 500
Ω
.
•
Voltages on Vin+, V/Iin-, and Iin+ of the 1769-IF4FXOF2F module must be
within +/-10V dc of analog common.
(1) In environments where high-frequency noise may be present, it may be necessary to directly ground cable shields to earth
at the module end and via a 0.1µF capacitor at the sensor end.
(2) Cable length over 50 meters may impact accuracy. For details, refer to the Compact Combination Analog I/O Module,
publication 1769-UM008A-EN-P.
ATTENTION
Be careful when stripping wires. Wire fragments that fall into a module
could cause damage at power up. Once wiring is complete, ensure the
module is free of all metal fragments.