NuDAQ ACL-8112 Series, Руководство пользователя

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Calibration & Utilities
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Table 6.1-1 Function of VRs
There are five variable resistors (VR) on the ACL-8112PG board to allow
you making accurate adjustment on A/D and D/A channels. The function
of each VR is specified as Table 6.1 -2.
VR1 D/A channel 1 full scale adjustment
VR2 D/A channel 2 full scale adjustment
VR3 A/D full scale adjustment
VR4 A/D programmable amplifier offset adjustment
VR5 A/D offset adjustment
Table 6.1-2 Function of VRs
6.3 A/D Adjustment
6.3.1. Bipolar Calibration
1. Set the analog input range as: +/- 5V, i.e. the gain = 1 and
input mode = Bipolar.
2. Short the A/D channel 0 ( pin 1 of CN3) to ground(GND), and connect
the TP1(+) and TP2(-) with your DVM. Trim the variable resister VR5 to
obtain a value as close as possible to 0V.( For ACL-8112DG, users
can skip this step)
3. Applied a +5V input signal to A/D channel 0, and trim the VR2 to obtain
reading between 4094~4095.
4. Applied a +0V input signal to A/D channel 0, and trim the VR1 to obtain
reading flickers between 2048~2049.
5. Repeat step 2 and step 3, adjust VR2 and VR1.
6.3.2. Unipolar Calibration
1. Set the analog input range as: 0 ~ 10 V, i.e. the gain = 1 and
input mode = U nipolar.
2. Applied a +10V input signal to A/D channel 0, and trim the VR6 to
obtain reading flickers between 4094 ~ 4095.