The PCM-3718H has been well calibrated at the factory for initial use. Users have no necessary to calibrate PCM-3718H in normal condition. However, in other conditions users may need to calibrate the PCM-3718H, then you can follow the process listed below.
To perform an effective calibration, a standard 4-1/2 digits resolution, stable and low-noise DC voltage source is necessary.
1. Running advdevice_calibrate utility
#advdevice_calibrate /dev/advdaq0
"/dev/advdaq0" is the device file which bound with a PCM-3718H using advdevice_bind utility. The screen will show as follows:
Advantech: PCM-3718 Calibration Utility
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Please check the items below before calibration:
a) First start D/A calibration, secondly A/D calibration
b) Jump "DA V.REF" to "INT"; Jump JP10 to "5V". This means the reference voltage source of D/A converter is connected to an on-board reference.
Please select your operation:_
1) D/A Calibration
2) A/D Calibration
3) Exit
You can select your operation by inputting different key values:
'1': select D/A calibration
'2': select A/D calibration
'3': exit
2. D/A calibration
Step 1: D/A offset
Advantech:PCM-3718 D/A Calibrating
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Please measure D/A output with a 4 1/2-digit multimeter.
Step 1: Adjust VR6 until the output voltage equals 0 V.
Please select your operation:_
1) Back 2) Next 3) Exit
You can select your operation by inputting different key values:
'1': Back
'2': Next
'3': Exit
Step 2: D/A full scale (gain)
Advantech: PCM-3718H D/A Calibrating
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Connect a reference voltage within the range +5 V to the reference
input of the D/A channel you want to calibrate. You can use either the on-board +5 Vreference or
an external reference. Please measure D/A output with a 4 1/2-digit multimeter.
Step 2: Adjust VR5 until the output voltage equals the reference voltage minus 1 LSB (+4.9988 V)!.
Please select your operation:_
1) Back 2) Next 3) Exit
You can select your operation by inputting different key values:
'1': Back
'2': Next
'3': Exit
Step 3: Finishing D/A calibration
Advantech: PCM-3718H D/A Calibrating
======================================
Step 5: The D/A calibration is finished
Please select your operation:
1) Back 2) Next 3) Exit
You can select your operation by inputting different key values:
'1': Back
'2': Next
'3': Exit
3. A/D Calibration wizard
Advantech: PCM-3718 Calibration Utility
==================================================
Please check the items below before calibration:
a) First start D/A calibration, secondly A/D calibration
b) Jump "DA V.REF" to "INT"; Jump JP10 to "5V". This means the reference voltage source of D/A converter is connected to an on-board reference.
Please select your operation:_
1) D/A Calibration
2) A/D Calibration
3) Exit
Step 1: PGA offset
Advantech: PCM-3718 A/D Calibrating
==================================================
Step 1: Short the A/D input channel 0 to ground and measure the voltage at TP1 on the PCB.
Adjust VR4 until TP1 is as close as possible to 0V
Please select your operation:_
1) Back 2) Next 3) Exit
Step 2: A/D bipolar offset
Advantech: PCM-3718 A/D Calibrating
==================================================
Step 2: Please connect a DC voltage source with value equal to 0V or
connect D/A output channel to A/D channel 0 (pin 1 connector CN3).
Adjust VR3 until the output from the card's A/D converter flickers between 2047 and 2048
AI channel 0 Value is [2247]
Please select your operation:_
1) Back 2) Next 3) Exit
Step 3: A/D full scale (gain)
Advantech: PCM-3718 A/D Calibrating
==================================================
Step 3: Please connect a DC voltage source a value of 5V orconnect D/A output
to A/D channel 0 (pin 1 on connnector CN3).
Adjust VR2 until the A/D reading flickers between 4094 and 4095
Repeat Step 2 to Step 3
AI channel 0 Value is [4095]
Please select your operation:_
1) Back 2) Next 3) Exit
Step 4: A/D unipolar offset
Advantech: PCM-3718 A/D Calibrating
==================================================
Step 4: Please connect a DC voltage source with value equal to 0V or
connect D/A output channel to A/D channel 0 (pin 1 connector CN3).
Adjust VR1 until the output from the card's A/D converter flickers between 0 and 1
AI channel 0 Value is [0]
Please select your operation:_
1) Back 2) Next 3) Exit
Step 5: Finishing A/D calibration
Advantech: PCM-3718 A/D Calibrating
==================================================
Step 5: The A/D calibration is finished!
Please select your operation:_
1) Back 2) Next 3) Exit