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CompactLogix Packaged Controllers
Publication 1769-IN082A-EN-P - July 2008
High-speed Counter Wiring Diagrams
Read and consider this information before wiring your high-speed counter.
•
Input and output channels are isolated from the packaged controller. Input
channels are isolated from one another; output channels are not.
•
Shielded cable is required for high-speed input signals A, B, and Z. Use
individually shielded, twisted-pair cable (or the type recommended by the
encoder manufacturer) for lengths up to 300 m (1000 ft).
•
Route field wiring away from any other wiring and as far as possible from
sources of electrical noise, such as motors, transformers, contactors, and AC
devices.
•
Routing field wiring in a grounded conduit can reduce electrical noise.
•
If field wiring must cross AC or power cables, ensure that they cross at right
angles.
•
Make sure the system is properly grounded using these guidelines:
–
This product is intended to be mounted to a well-grounded mounting
surface such as a metal panel. Additional grounding connections from the
packaged controller’s mounting tabs or DIN rail (if used) are only
required when the mounting surface is non-conductive and cannot be
grounded.
–
Keep the shield connection to ground as short as possible.
–
Ground the shield drain wire only at the HSC input end, except where
high-frequency noise is present.
•
To establish optimum accuracy, limit overall cable impedance by keeping
cable as short as possible. Locate the packaged controller as close to input
devices as your application permits.
ATTENTION
Disconnect power before wiring the HSC removable terminal block. This includes sensor
and packaged controller power.
IMPORTANT
In environments where high-frequency noise may be present, it may be necessary to
directly ground cable shields to earth at the removable terminal block end and via a 0.1µF
capacitor at the sensor end.
