Spectrum Controls 1769sc-HART Modules - Manual (Page 15)

Chapter 2: Quick Start For Experienced Users
User's Manual 0300215-03 Rev. A
2-3
5. To allow communication between the controller and module, move the bus lever
fully to the left (4) until it clicks. Ensure it is locked firmly in place.
6. Attach an end cap terminator (5) to the last module in the system by using the
tongue-and-groove slots as before.
7. Lock the end cap bus terminator (6).
!
Attention
When attaching I/O modules it is very important that the bus connectors
are securely locked together to ensure proper electrical connection.
!
Attention
A 1769-ECR or 1769-ECL right or left end cap respectively must be used
to terminate the end of the 1769 communication bus.
Step 3: Wire the module. Reference
Chapter 3 (Installation and Wiring)
Follow the guidelines below when wiring the module.
General
•
Power and input wiring must be in accordance with Class 1, Division 2 wiring
methods, Article 501-4(b) of the National Electric Code, NFPA 70, and in
accordance with the authority having jurisdiction.
•
Channels are isolated from one another by ±500V dc maximum.
•
Route field wiring away from any other wiring and keep it as far as possible from
sources of electrical noise, such as motors, transformers, contactors, and ac devices.
As a general rule, allow at least 15.2 cm (6 in.) of separation for every 120V of
power.
•
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.
Terminal Block
•
For voltage and current sensors, use Belden 8761 shielded, twisted-pair wire (or
equivalent) to ensure proper operation and high immunity to electrical noise.
•
To ensure optimum accuracy, limit overall cable impedance by keeping a cable as
short as possible. Locate the module as close to input devices as the application
permits.
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.
•
Keep cable shield connections to ground as short as possible.
•
Ground the shield drain wire at one end only. The preferred location is as follows.
•
Refer to Industrial Automation Wiring and Grounding Guidelines, Allen-Bradley
publication 1770-4.1, for additional information.