Instruction manual

Power-Supply and Sensor Wiring
continued
RFT9739 Rack-Mount Transmitter Instruction Manual 19
Output Wiring Startup TroubleshootingBefore You Begin Getting Started Mounting
Power-Supply and
Sensor Wiring
Grounding
To ensure proper grounding:
• If the sensor installation must comply with UL or CSA standards, refer
to the instructions in one of the following Micro Motion documents:
-
UL-D-IS Installation Instructions
-
CSA-D-IS Installation Instructions
• To determine which grounding instructions to use, refer to
Table 4-1
.
Table 4-1.
Selecting the proper
grounding scheme
Figure 4-2a. Grounding detail — typical
CAUTION
Failure to comply with requirements for intrinsic
safety if the sensor is installed in a hazardous area
could result in an explosion.
The transmitter must be properly grounded. Follow the
instructions below to ground the transmitter.
Condition Figure Page
Sensor is installed in a non-hazardous area 4-2a 19
Sensor is installed in hazardous area,
plant does
not
have a separate intrinsically safe ground system,
installations in Europe only
4-2a 19
Sensor is installed in a hazardous area,
any area except Europe
4-2b 20
Plant uses a separate, high-integrity, I.S. ground scheme 4-2c 20
Ground wire
Earth
ground
If national standards are not in effect, adhere
to these guidelines for grounding:
• Use copper wire, 14 AWG (2.5 mm²) or
larger wire size.
• Keep all ground leads as short as possible,
less than 1 ohm impedance.
• A factory-installed ground wire, connecting
the I.S. ground and power-supply ground
terminals, must remain in place.
• Connect power-supply ground directly to
earth.
• For hazardous area installation in Europe,
use standard EN 60079-14 as a guideline.
• To achieve potential equalization and comply
with CENELEC standards for hazardous
area installations in Europe, connect power-
ground terminal to the appropriate ground
terminals within the hazardous area, using a
potential equalizing line.