Emerson Rosemount 702 - Grounding the Transmitter

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Reference Manual
00809-0200-4702, Rev CA
Section 3: Mounting, Wiring Switches, and Sensors:
Models 702DX22 and 702DX61
February 2013
Mounting, Wiring Switches, and Sensors:
Models 702DX22 and 702DX61
3.5 Grounding the Transmitter
The 702 transmitter operates with the housing grounded or floating. Floating systems,
however, can cause extra noise that may affect many types of readout devices. If the signal
appears noisy or erratic, grounding at a single point may solve the problem. Grounding of the
electronics enclosure should be done in accordance with local and national installation codes.
Grounding is accomplished through the process connection using the internal or external case
grounding terminal.
Determining Grounding Requirements
Each process installation has different grounding requirements. Use the options recommended
by the facility for the specific switch type, or begin with Option 1, which is the most common.
Option 1:
1. Connect switch wiring shield to the grounded transmitter housing.
2. Ensure that the transmitter housing is electrically isolated from the switch wiring.
Option 2:
1. Ground switch wiring shield at the switch.
2. Ensure that the switch wiring and shield are electronically isolated from the transmitter
housing.
NOTE
Always use facility recommended wiring practices.