Heise PTE-2, Руководство по эксплуатации и обслуживанию

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Pressure modules can be recalibrated and certified in the field.
The procedure allows for the acquisition of “as found” and “as left”
data, and recalibration of the pressure module.
Field calibration typically consists of three steps. Step one is
to document the “as found” or pre calibration condition of the
module. Step two is to perform the recalibration procedure to
adjust coefficients used by the module. Step 3 is to repeat step
one to document the “as left” or post recalibration condition of the
module.
The procedure details two processes, first obtaining “as found”
and ”as left” data; second performing the actual calibration of the
HHC.
Obtaining “As found” and “As Left” data consists of applying
precisely controlled pressure to the module and comparing the
value shown on the display to that being applied by the pressure
standard. The number of points measured typically increases with
the accuracy of the module. Factory calibration consists of the
following number of points based on module accuracy:
0.025% & 0.05% enhanced accuracy
20 points (approximately 10% increment)
0.025% - 0.07% standard accuracy
11 points (approximately 10% increment)
0.1% standard accuracy
6 points (approximately 20% increment
0.25% standard accuracy
5 points (approximately 25% increment)
When calibrating linearity, the HHC will automatically choose the
number and pressure value of data points based on the module’s
full scale pressure range and it’s base accuracy specification.
Pressure module recalibration is a firmware based, menu driven
procedure that provides prompts on the HHC display directing
the operator to apply precision pressure at zero, full scale and
several cardinal points, the quantity of which is determined by
the accuracy specification of the module. Module recalibration is
accessed via the menu system.
NOTE Following Pressure Module Calibration, damping is auto-
matically set to 16 (maximum.). To reduce the damping level to
1 (minimum), power cycle the HHC, or remove and reinstall the
pressure module.
REQUIRED EQUIPMENT
A Precision Pressure standard must be used to maintain the
stated accuracy of the pressure module. It is recommended to
have the pressure standard accuracy 4 times better, than the
accuracy of the calibrated module.
PRESSURE MODULE FIELD CALIBRATION PROCEDURE
1. Insert Pressure Module to be calibrated into the CH 1 Module
bay (left bay, when the HHC faces the operator with module
bays up).
2. Turn the base unit on by pressing the green “ON/OFF” button
on the keypad
3. Initiate the calibration process as follows:
a. Press MENU key
b. Press DOWN or UP ARROW key to highlight “Setup…”
c. Press ENTER
d. Press DOWN or UP ARROW key to highlight “Calibrate”
e. Press ENTER
Cal Password screen appears. Enter Calibration Password
SECTION 15 o. PRESSURE MODULE CALIBRATION