Level Calibration; Standard Level Calibration; Level Calibration With A Tank Top Reference Stop - Honeywell 854 ATG Series Instruction Manual

3.4 Level calibration

3.4.1 Standard level calibration

Make sure the displacer is at the liquid surface. Perform a repeatability test to ensure the displacer is on the
product surface (refer to section 4.2).
Determine the product level by manual dipping. It is essential that the level is as stable as possible.
Note:
Make two or three manual dips and compare each reading to ensure the manual dip value is correct.
Item Name
W2= Protection level 2
RL= Reference level
AR Accept reference
EX Exit

3.4.2 Level calibration with a tank top reference stop

A tank top reference stop is a mechanical device that can hold the displacer at a reproducible position when
the displacer is pulled up. This device is placed above the motor limit switch high position. An Honeywell
Enraf tank adapter can be provided with such a facility.
1) Follow the procedure as described in section 3.4.1
2) Determine the tank top position; proceed as follows:
Item Name
W2= Protection level 2
CA Calibrate
TT= Tank top
EX
Exit
For verification of the level calibration, refer to section 4.8.1.
Instruction manual 854 ATG
Description
Enter the protection level 2 password
Format according to item LD. Enter in this item the manual level.
By giving this command, the level value entered in item RL, is
accepted as product level and will be shown on the display.
Exit protection level.
Description
Enter the protection level 2 password.
With this command the displacer is pulled up until it is halted against
the tank top reference. Wait until the displacer is settled.
Format according to item LD. Read the level value from the display
and program that value in item TT.
Exit protection level.
Commissioning
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