Rosemount 702, Справочное руководство

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Reference Manual
00809-0200-4702, Rev BA
June 2010
Rosemount 702
3-10
GROUND THE
TRANSMITTER
The Rosemount 702 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.
Switch Inputs
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.
Float Switch
Shield ground point
702 Transmitter
Shield ground point
702 Transmitter
Float Switch