DH Instruments MFC-CB, Руководство по эксплуатации и обслуживанию

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION
Page 79
©2001~2007 DH Instruments, a Fluke Company
5.2.2 FRONT PANEL ADJUSTMENT OF ELECTRICAL SIGNALS
5.2.2.1 PRINCIPLES
See Section 5.2.1 for general information on the principles of MFC-CB electrical
signal adjustment.
MFC-CB provides front panel capability to mathematically adjust each of the MFC-CB
electrical output and input signals. The adjustments are accomplished by an
adder
and
multiplier
that is used to offset and adjust the slope of each signal’s response.
The
adder
(A) and
multiplier
(M) affect the signal as follows:
Corrected Value = (Uncorrected Value X Multiplier) + Adder
Where:
•
Corrected value, uncorrected value and
adder
are in the current unit of measure.
•
Multiplier
is dimensionless.
[SPECIAL] , <4cal> provides capabilities to view each electrical signal value real time
and edit its
adder
and
multiplier
. To calibrate or adjust the electrical signals, compare
their values to a reference and adjust the corresponding
adder
and/or
multiplier
as
needed to arrive at acceptable agreement.
As editing adder and multiplier values alters MFC-CB’s calibration, they should only
be edited by qualified personnel as part of the calibration process. Caution should be
taken to avoid accidental editing. For information on preventing access to calibration
information, see Section 3.4.2.
A new MFC-CB is delivered with all calibration adder and multiplier values set to
zero (0) and one (1) respectively. This does NOT mean that the MFC-CB has NOT
been calibrated. For the original factory calibration, privileged factory coefficients are
used for calibration adjustment. This allows a new MFC-CB to be delivered with
“virgin” calibration coefficients of
A = 0 and M = 1 for all signals.
To facilitate signal verification and calibration, the view screens of the MFC-CB local
calibration function ([SPECIAL], <4cal>) display the device channel electrical signals
affected only by their calibration adder and multiplier . K factor and adjustment
factors are NOT applied (see Section 7.1).
See Section 7.2 for MFC-CB device channel connector pin outs.