Emerson Vilter MicroVission, Руководство по эксплуатации и обслуживанию

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8 – 1
Section 8 • Instruments Calibration
MicroVission Controller • Operation and Service Manual • Emerson • 35391MV 1.0
Overview
The Instrument Calibration screen allows the operator
to define how the MicroVission will interpret the signal
from any devices connected to panel’s analog inputs.
The Instrument Calibration screen is organized in four
pages. Each page is then divided into individual tabs for
every device.
I/O
Each tab has this section that provides basic information
for that device.
A/D bit Value
This field displays the actual value read by MicroVission
analog to digital convertors. This value is unaffected by
any changes to the calibrations settings. If a device is
connected to the associated input, there will be some
value displayed in this field.
Calibrated Value
This field displays the calibrated value which is the result
of the calibration process. Calibrated value for Pressure
& Temperature values will be displayed in pressure / tem-
perature unit as configured in Configuration Screen.
All instruments are calibrated using a two-point linear
calibration process. Any device that has a non-linear re-
sponse to environmental stimuli will not be able to be
calibrated through the MicroVission.
Pressure & Temperature Inputs
The most commonly used Instruments are pressure
and temperature sensors. The first two pages of the
Instrument Calibration Screen are dedicated to these
Instruments; see Figure 8-1 up to Figure 8-12.
Each tab on these two pages are divided into two sec-
tions, Device Calibration and Channel Calibration.
Devices Calibration
The Device Calibration section is where the operation
parameters of the Instrument are defined.
Default Devices
By selecting this option, the operator will have access
to several common devices via a drop-down list. The
devices are predefined and if one is selected, then all
the setpoints will be set for the operator.
Custom Device
This option allows the operator to choose the minimum
and maximum value of the Instrument being used.
The Instrument Calibration screen provides a set of rang-
es for default devices. You must select an appropriate
range to calibrate the sensor. If you do not find a correct
range, you can specify the custom range.
Based on the calibration range that you select or specify,
the MicroVission displays the calibrated value. This cali-
brated value of the respective analog input is also shown
on the Main screen.
Channel Calibration
The Channel Calibration section defines the type of sig-
nal sent by the Instrument.
Offset
Once the two-point calibration is completed, it is com-
mon for a small error to exist. By entering the value of
the error from the calibrated value and the actual value
into the “Adjustment” entry box, that error will be add-
ed/subtracted from the “Total Offset”. The offset is ap-
plied to the calibrated value which should correct the
error.
Range
This option is available when the “Custom Device” op-
tion is selected. Here the operator defines the signal
type and range transmitted by the Instrument. The op-
erator can select from several predefined ranges in the
drop-down list or enter a value.