Honeywell HERMetic UTImeter Gtex Chem, Руководство по эксплуатации и обслуживанию

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9.12 Reference height / innage measurement
If the unit is fitted with the additional load (see Figure 9-8) then
reference height / innage measurement are possible.
• Install the HERMetic equipment as per 9.9 “Installation of the
instrument”.
• Open the valve by turning the handle.
• Put the tape cleaner on the “DOWN” position. Disengage
the knob of the crank handle and lower the sensing probe
into the tank by turning the reel. Make sure that the tape
does not rub on any sharp edge when lowering as its
insulation could be damaged.
• When the sensing probe comes in contact with the dip/
datum plate record the distance shown on the reading index.
See Figure 9-9. The exact distance from the plate to the
reading index is (r 4 mm) or (r 5/32”) which
is the reference height providing the reading index level has
been adjusted to the zero ullage level of the tank. If the tank
zero ullage is levelled above or below the reading index, an
additional correction shall apply. For more details refer to
section “Installation of the gauging system”.
• Turn the tape cleaner on “UP” position.
• Switch on the unit and raise up the sensing probe until
checking the oil/water interface if any (see details in section
9.11 ”Ullage / interface measurement”). To get a better
accuracy of the interface level, release the tape cleaner on
the “DOWN” position during the final checking. Calculate
the free water height by subtracting the index reading to the
reference height.
• Reengage the tape cleaner on the “UP” position and raise
up the sensing probe until checking the ullage (see details in
section 9.11 “Ullage / interface measurement”). Release the
tape cleaner for final checking of the ullage. Calculate the
innage by subtracting the index reading and the free water
height to the reference height determined before.
• When the measurements are completed, switch off the unit,
engage the tape cleaner on the “UP” position and wind up
the tape until the sensing probe is in the storage tube. The
reading on the tape shall be less than 420 mm or 1 ft 5 inch.
• Close the valve and disconnect the instrument from the nipple.
• Put the end cap back on the valve.
Figure 9-8
+ 4 mm (5/32")
=
+ 4 mm (5/32")
100
200
300
400
500
600
700
800
900
1000
1100
1200
0
Tape reading
Distance from dip/datum plate
to reading index
sensor
with load
Dip/Datum plate
Figure 9-9