Rosemount 3095, Product Manual

Page: 32 / 115

Rosemount Model 3095 Multivariable
™
Level Controller
2-22
5. Plug and seal unused conduit connections on the Level Controller
housing to avoid moisture accumulation in the terminal side of the
housing. The unused conduit opening on the controller housing
must be plugged and sealed to meet explosion-proof requirements.
NOTE
If the conduit connections are not sealed, mount the Level Controller
with the electrical housing positioned downward for drainage. Conduit
should be installed with a drip loop, and the bottom of the drip loop
should be lower than the conduit connections or the controller housing.
Install Field Wiring
Grounds Field wiring may be grounded at any one point on the signal loop, or it
may be left ungrounded. The negative terminal of the power supply is a
recommended grounding point.
The controller case should always be grounded in accordance with
national and local electrical codes. The most effective controller case
grounding method is direct connection to earth ground with minimal
impedance. Methods for grounding the controller case include:
•
External Ground Assembly
: This assembly is included with the
transient protection terminal block. The External Ground
Assembly can also be ordered as a spare part (03031-0398-0001).
•
Internal Ground Connection
: Inside the FIELD TERMINALS
side of the electronics housing is the Internal Ground Connection
screw. This screw is identified by a ground symbol:
.
NOTE
The transient protection terminal block does not provide transient
protection unless the controller case is properly grounded. Use the
above guidelines to ground the controller case.
Do not run the transient protection ground wire with field wiring as the
ground wire may carry excessive current if a lighting strike occurs.
Grounding the controller case using threaded conduit connection may
not provide sufficient ground.
Replace Cover Replace the Level Controller cover. Both controller covers must be fully
engaged to meet explosion-proof requirements.
CALIBRATION The Level Controller does not require any bench or field calibration.
The differential pressure sensor has been factory calibrated from
– URL to + URL.
After installation, a standard level trim (offset and slope) must be
completed (see page 4-10).