Verify Level Calibration; Verify Level Calibration Against A Tank Top Reference Stop; Verify Level Calibration On Top Of Ball Valve - Honeywell 854 ATG Series Instruction Manual

4.9 Verify level calibration

4.9.1 Verify level calibration against a tank top reference stop

When a tank adapter with a tank top reference stop is installed, the level calibration of the 854 ATG can be
checked. Proceed as follows:
Item Name
CA Calibrate
TT Tank top
UN Unlock
If the tank top value and the gauge reading differs more than the specified value, the calibration procedure as
described in section 3.4.2 should be repeated.

4.9.2 Verify level calibration on top of ball valve

If the top of the ball valve is used as reference point, the level calibration of the 854 ATG can be verified.
Proceed as follows:
Item Name
CA Calibrate
UN Unlock
RL Reference level
CA Calibrate
UN Unlock
If the reference level value and the gauge reading differs more than the specified value, the calibration
procedure as described in section 3.4.3 should be repeated.
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Description
With this command the displacer is pulled up until it is halted
against the tank top reference. Wait until the displacer is settled.
Request for the tank top value, which was established during level
calibration. The level reading from the gauge should not differ more
1
than ±3 mm (± / ") with the value in item TT.
8
Give an unlock command to cancel the calibrate command.
Description
The displacer will be raised until it stops against the flange of the
level gauge.
If a 45 mm displacer is used, stop immediately the Calibrate command
as soon as the displacer is above the ball valve,
followed by an FR (freeze) command.
Make sure the displacer is positioned above the ball valve.
►
Close the ball valve.
Unlock the gauge and wait the displacer reaches the top of the ball
valve.
Request for the reference level value, which was established during
calibration. The level reading from the gauge should not differ more
1
than ±2 mm (± / ") with the value in item RL.
16
The displacer will now raise from the ball valve.
Let it stop against the flange or give a FR (freeze) command.
Open the ball valve.
►
Give an unlock command to cancel the calibrate command.
Caution
Operation