Spectrum 1734, Руководство пользователя

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2-8 Chapter 2: Installation and Wiring
User’s Manual Pub. 0300272-03 Rev. B
Section 2.5
Field Wiring
Connections
Consider the following when wiring your system:
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.
•
Use Belden™ 8761 or equivalent, shielded wire.
•
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.
•
Digital and analog power must be supplied by an Isolated Secondary
Limited Energy Low Voltage source.
Outputs
The module provides loop power for analog outputs.
Grounding
WARNING
USE SUPPLY WIRES SUITABLE FOR 10 °C ABOVE
SURROUNDING AMBIENT TEMPERATURE.
WARNING
UTILISER DES FILS D’ALIMENTATION QUI CONVIENNENT A
UNE TEMPERATURE DE 10 °C AU-DESSUS DE LA
TEMPERATURE AMBIANTE.
•
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.
•
Under normal conditions, the drain wire (shield) should be connected
to the metal mounting panel (earth ground). Keep shield connection
to earth ground as short as possible.
•
Ground the shield drain wire at one end only. The typical location is
as follows:
-
For grounded thermocouples or millivolt sensors, this is at
the sensor end.
-
For insulated/ungrounded thermocouples, this is at the
module end. Contact your sensor manufacturer for additional
details.
Refer to Industrial Automation Wiring and Grounding Guidelines,
Allen-Bradley publication 1770-4.1, for additional information.