SCC-LP Series Lowpass Filter Modules User Guide
16
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Calibrating Gain Errors
The SCC-LP
XX
is calibrated at the factory before shipment. If you want to
calibrate the SCC-LP
XX
in your system, you need a voltage source capable
of providing a DC voltage up to
±
10 V that is several times more accurate
than the SCC itself.
To calibrate the SCC-LP
XX
, complete the following steps for each channel
of the module:
1.
Select the desired SCC-LP
XX
channel (
X
or
X
+
8) on the E Series DAQ
device.
2.
Set the gain on the E Series DAQ device so that the E Series input
range is
±
5 V.
3.
Connect the voltage source to the screw terminals of the desired
channel on the SCC-LP
XX
.
4.
Input 9 VDC to the SCC-LP
XX
.
5.
Using your software, have the E Series DAQ device read the desired
channel on the SCC-LP
XX
. Record the value.
6.
Input 0 VDC to the SCC-LP
XX
.
7.
Have the E Series DAQ device read the channel again and record the
new value.
8.
Calculate the difference between the two values you recorded
(
first reading
–
second reading
).
9.
Adjust the appropriate trimpot (
X
or
X
+
8) on the top of the SCC-LP
XX
.
Repeat steps 4 through 8 until the difference you get in step 8
equals 9 V.
For example, you connect 9 VDC to the input of CH (
X
) and the E Series
DAQ device reads 9.05 V at the SCC output; then you connect 0 VDC to
the input of CH (
X
) and the E Series DAQ device reads –0.01 V at the SCC
output. Subtract the second value from the first (9.05 – (–0.01)) to get a
difference of 9.06 V. Because the difference is not equal to 9 V, you adjust
the trimpot until the difference in outputs equals 9 V.
Note
In this example there may be an offset voltage such that the final voltages are 9.01 V
and 0.01 V for a difference of 9 V. The SCC-LP
XX
trimpot adjusted in step 9 adjusts only
for gain errors and does not compensate for this offset voltage.
Содержание SCC-PWR02
Страница 1: ...SCC PWR02...
