User Manual

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9.14 Setting the 8947 CHARGE UNIT
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9
.14.2 Setting the Sensor Sensitivity
EU/V : 1/9.8 = 0.1020E+00
Offset : 0.0000E+00
EU : G
Conversion ratio metho
d
9.8000E+00 → 1.0000E+00
0.0000E+00 → 0.0000E+00
EU : G
2-point metho
d
EU/V : 10/23.4 = 0.4274E+00
Offset : 0.0000E+00
EU : m/s
2
Conversion ratio method
2.3400E+01 → 1.0000E+01
0.0000E+00 → 0.0000E+00
EU : m/s
2
2-point metho
d
Sensor sensitivity is set in meters-per-second squared (m/s
2
) units. However,
some acceleration sensors use G (gravitational constant) units, in which case
the read value should be divided by 9.8 (m/s
2
).
Example 1
If specified sensor sensitivity is written as 1.08 (pC/(m/s
2
));
sensor sensitivity level should be set to 1.08.
Example 2
If specified sensor sensitivity is written as 64.0(pC/G);
64.0 / 9.8 ＝ 6.53 (pC/(m/s
2
))
sensor sensitivity level should be set to 6.53.
■About Units
This device normally measures in units of charge level per m/s
2
, but the units
can be changed to charge level per G by the scaling function. Scaling can be
set as follows:
Refer to Section 9.7 for the detail settings.
■Using a sensor outside of the setting range
The setting range of sensor sensitivity is 0.1 to 10 pC/(m/s
2
) or 0.1 to 10
mv/(m/s
2
), but a sensor operating outside of this range can be used by enabling
scaling.
(1) Display the CHANNEL1 screen, and set the sensor sensitivity. Multiply
the actual sensor sensitivity to be used by the appropriate factor to produce
a settable number (0.1 to 10), and enter that factor.
(2) Display the SCALING screen, and turn on Charge or Preamp mode for the
channel using the sensor that is outside of the setting range.
(3) Set the same conversion ratio as the sensor sensitivity factor.
Example 1
Sensor sensitivity is 23.4 pC/(m/s
2
):
・Multiply sensor sensitivity by 1/2.34 and set 10 pC/(m/s
2
) as the sensor
sensitivity.
・Set the scaling.