Rockwell Automation 1769-IF4XOF2 Compact 8-Bit Low Resolution Analog I/O Combination Module - Manual (Page 32)

Publication 1769-UM008A-EN-P - November 2001
3-10 Installation and Wiring
Field Wiring Connections Grounding
This product is intended to be mounted to a well-grounded mounting
surface such as a metal panel. Additional grounding connections from
the module’s mounting tabs or DIN rail (if used) are not required
unless the mounting surface cannot be grounded. Refer to Industrial
Automation Wiring and Grounding Guidelines, Allen-Bradley
publication 1770-4.1, for additional information.
System Wiring Guidelines
Consider the following when wiring your system:
General
•
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)
Inputs
•
If multiple power supplies are used with analog inputs, the
power supply commons must be connected.
•
The 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.
•
Voltages on Vin+, V/Iin-, and Iin+ of the module must be within
0 to +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.