AB Quality Allen-Bradley 1771-IJ, User Manual

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3–2 Installation
Publication 1771ĆUM006B-EN-P - June 2002
!
ATTENTION
Preventing Electrostatic Discharge
This equipment is sensitive to electrostatic
discharge, which can cause internal damage and
affect normal operation. Follow these guidelines
when you handle this equipment:
•
Touch a grounded object to discharge
potential static.
•
Wear an approved grounding wriststrap.
•
Do not touch connectors or pins on
component boards.
•
Do not touch circuit components inside the
equipment.
•
If available, use a static–safe workstation.
•
When not in use, keep modules in appropriate
static–safe packaging.
The module may be placed in any 1771 I/O chassis. However, the
module must only be inserted in a single module group; it cannot
straddle two groups. To minimize noise, group low voltage input
modules together within a single I/O chassis whenever possible.
!
WARNING
Remove power from the I/O chassis backplane and
wiring arm before removing or installing a module.
•
Failure to remove power from the backplane
could cause unexpected machine operation with
possible damage to equipment or injury to
personnel. It could also damage the module or
degrade performance.
•
Failure to remove power from the wiring arm
could damage the module or degrade
performance.
Use the proper cable to connect the input devices to the module field
wiring arm. Follow the appropriate connection diagram (Figure 3.1
and Figure 3.2). Input devices cannot be more than 40 cable feet
from the module.
Use Belden 8761 cable for pulse counter applications with a signal
below 20K Hz; use Belden 9182 cable for frequencies up to 50k Hz.
Use Belden 8725 cabe (4-twisted pair cable) for encoder applications
below 20k Hz.
Module Placement
Recommended Cable