Installing The Lwt Instrument; Rotating The Housing - ABB LWT300 Series User Manual

Installing the LWT instrument

NOTICE
Installing the LWT system directly on the top of the vessel provides the best return
signal.
Once the probe and coupler/head assembly have been attached, you need to:
1 Insert the probe end into the flange, down the nozzle and to the bottom of the vessel.
2 Secure the coupler as necessary:
– If you have an NPT-style coupler, apply a proper sealant on the NPT threads and screw the coupler
in the NPT flange.
NOTICE
As much as possible, avoid using PTFE tape on the threaded connection as this type
of tape can affect the ground connection between the coupler and the tank. If PTFE
tape is used, it shall be used in a very thin layer to avoid electrically isolating the
coupler from the tank.
– If your coupler came in a flanged configuration, make sure that the appropriate gasket is installed
before inserting the coupler assembly, and secure the flange with the appropriate nuts and bolts
to the torque required by the flange class.

Rotating the housing

To improve HMI visibility or field access to the wiring, you may rotate the LWT housing 360° from its
initial position, and secure it in any of these positions.
To rotate the housing:
1 With an hexagonal key, slightly loosen the head adapter security screw (less than one full turn) (see
Figure 10).
—
Figure 10 Rotating the housing
M4 hex head
locking screws
Head adapter
Head adapter security screw
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Installing the LWT