Ectron 451, Инструкция по эксплуатации

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SELECTING THE OPERATING MODE TO USE
There are three operating modes to choose from: gain, example, and scale. The choice of
which mode to use depends on several factors: whether the transducer sensitivity of the
transducer is known, whether physical measurements can be made on the movement of the
transducer when it is in place, the desired accuracy of the resulting data, etc.
Gain Mode This mode can be used if the transducer sensitivity of
the LVDT or RVDT and the gain needed for the test
are known, or if experimentation with gain settings to
see if the resulting output swing fits the intended
application can be done.
Enter the transducer sensitivity and set the gain to the
specified value (these two steps can be done in either
order). If possible, do a preliminary test to determine
if the output fits the required output range. Note: if the
output polarity is the reverse of that which is expected,
change the polarity of the gain setting. The allowable
gain range is from
−
1 to
−
300 and +1 to +300 (less
than unity gain is not supported).
Example Mode
To set up this mode of operation requires that data for
two values of output voltage are entered along with the
corresponding positions of the apparatus under test. For
instance, if an output of 00.00 to +10.00 volts is required
for a movement of the apparatus from its minimum to
its maximum displacement, then from
EXAMPL
POINT1 VOLTS
, press the display, enter 00.00, change
the N (no) to Y (yes) and press the display. Repeat this
process for
EXAMPL POINT2 VOLTS
entering 10.00.
Next, you will be asked for two displacements. Move
the apparatus to its position where an output voltage of
00.00 is desired, select
EXAMPLE POINT1 DISP ,
press the display to
PT1 D EXAMPL SET N
, change
the N (no) to a Y (yes), and push the display. Point 1
displacement has been “ captured.” In a similar fashion
“ capture” Point 2 displacement.
This procedure equates the output voltages for Points
1 and 2 with the displacements for Points 1 and 2. The
processor precisely calculates the gain and offset values
necessary to match the Model 451 to the voltage and
displacement values entered.
It is not necessary to use the extremes of the displace-
ment values for the capture points. In the above example,
we could have used voltage points of 1.00 V and 9.00
V as long as the capture points were similarly modified.
Note, too, that Point 1 could be the higher voltage with
the lower displacement point; and Point 2, the lower
voltage with the higher displacement point.
Model 451 Applications
4-3