Chapter 4 Grounding - Emerson MICRO MOTION T-SERIES Installation Manual

4 Grounding
The sensor must be grounded according to the standards that are applicable at the site.
The customer is responsible for knowing and complying with all applicable standards.
Prerequisites
Micro Motion suggests the following guides for grounding practices:
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If no external standards are applicable, follow these guidelines to ground the sensor:
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CAUTION!
Ground the flowmeter to earth, or follow ground network requirements for the facility.
Improper grounding can cause measurement error.
Procedure
Check the joints in the pipeline.
- If the joints in the pipeline are ground-bonded, the sensor is automatically grounded
and no further action is necessary (unless required by local code).
- If the joints in the pipeline are not grounded, connect a ground wire to the grounding
screw located on the sensor electronics.
Tip
The sensor electronics may be a transmitter, core processor, or junction box. The grounding
screw may be internal or external.
Installation Manual
In Europe, IEC 79-14 is applicable to most installations, in particular Sections
12.2.2.3 and 12.2.2.4.
In the U.S.A. and Canada, ISA 12.06.01 Part 1 provides examples with associated
applications and requirements.
Use copper wire, 14 AWG (2,0 mm
Keep all ground leads as short as possible, less than 1 Ω impedance.
Connect ground leads directly to earth, or follow plant standards.
2
) or larger wire size.
Grounding
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