Wiring Precautions; Signal Wiring - Emerson Rosemount 700XA Quick Start Manual

Quick Start Guide
3.3 Gas chromatograph wiring
3.3.1 Wiring precautions
• All wiring, as well as circuit breaker or power disconnect switch
locations, must conform to the Canadian Electrical Code (CEC)
or National Electrical Code (NEC); all local, state, or other
jurisdictions; and company standards and practices.
• Provide single-phase, three-wire power at 115 or 220 Vac, 50-60
Hz.
Note
If you do not have a single phase, three-wire AC power source,
you must purchase an isolation transformer.
• Locate a power shut-off or disconnect switch in a safe area.
• Provide the gas chromatograph (GC) and any optionally installed
devices with one 20-amp circuit breaker for protection.
Note
15 amps is the maximum current for 14 American Wire Gauge
(AWG).
• Ensure that the 24 Vdc input power is compliant with the
separated extra-low voltage (SELV) standard by suitable electrical
separation from other circuits.
• Use multi-stranded copper conductor wire according to the
following recommendations:
— For power feed distances up to 250 ft. (76 m), use 14 AWG (18
metric wire gauge [MWG]), stranded.
— For power feed distances 250 ft. (76 m) to 500 ft. (152 m), use
12 AWG (25 MWG), stranded.
— For power feed distances 500 ft. (152 m) to 1000 ft. (305 m),
use 10 AWG (30 MWG), stranded.
3.3.2 Signal wiring
Follow these general precautions for field wiring digital and analog
input/output (I/O) lines:
• For shielded signal conducting cables, shield-drain wires must not
be more than two American Wire Gauge (AWG) sizes smaller than
the conductors for the cable. Shielding is grounded at only one
end.
• Metal conduit or cable (according to local code) used for process
signal wiring must be grounded at conduit support points,
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November 2023
Emerson.com