Robertshaw 5318B, Инструкция по эксплуатации, Страница: 9 / 30

MODEL 5318B INSTRUCTION MANUAL
Level Tek II , Capacitance Level Switch 909GF295
Page 3
SECTION III – INSTALLATION
3.1 GENERAL
Examine the instrument for possible shipping
damages.
IMPORTANT : If for any reason it is determined
that parts should be returned to the factory,
please notify the nearest Robertshaw Industrial
Products sales representative prior to shipment.
Each unit must be properly packed to prevent
damage. Robertshaw assumes no responsibility
for equipment damage in shipment due to
improper packaging.
Choose a location in accordance with good
instrument practice, avoiding extremes of
temperature, humidity, and vibration. (See
“Specifications”, Section II)
3.2 PROBE MOUNTING
Robertshaw probes are purchased separately
from the instruments and are available in a
variety of sizes and types with numerous options
for the materials and construction. Each probe
should be selected for the specific application in
order to insure the best and most reliable
operation of the system.
Probes are available with, or without insulation.
Insulated probes may be used for liquid, solid or
interface detection and can also be used on
conductive materials. Bare probes are normally
used on non-conductive materials only.
Standard type probes are installed so that the
face of the packing gland is flush (or nearly so)
with the vessel wall. When installing a probe in
a nozzle, recess or open end well, a sheathed
probe should be used, with the sheath length
equal to the nozzle, recess, or well length. This
insures that the “active” portion of the probe is
extended into the process area and eliminates
potential problems due to build-up in the nozzle,
recess, or well.
CAUTION: When installing an insulated probe,
care should be taken not to accidental puncture
the probe insulation.
3.2.1 HORIZONTAL MOUNTING
Horizontally mounted rod-type probes must be
installed in vessels at the desired point of level
detection. Horizontally mounted probes provide
the closest control (smallest deadband) in that a
small change at, or near, the probe will produce
a large capacitance change.
On applications involving viscous liquids, or
materials, that have a tendency to “cling” or
“build-up”, it is recommended that the probe be
mounted on a slight downward angle to permit
draining of the material from the probe.
Figure 3-1 Horizontally Mounted Instrument
3.2.2 VERTICAL MOUNTING
Vertically mounted rod-type probes should be
installed in either the top or bottom of the vessel
with the midpoint on the probe corresponding to
approximately the desired level detection point.
Vertically installed probes allow a variation in the
level detection point up and down the length of
the probe by means of the instrument
calibration.
Figure 3-1 Vertically Mounted Instrument