GW Instek GDM-8245 - Frequency Response Adjustment

GDM-8245 Service Manual
58
1kV
1000V@50Hz
1000V±4 digits
Note
The Up and Down arrow keys can be used to change the
DMM range up and down.
Calibrating the frequency response is complete.
Frequency Response Adjustment
Accepted range
±10 digits (all ranges excluding 1kV)
Equipment
 Multimeter calibrator
 Test leads
Configuration
Caution
The following service procedure involves the use of high
voltages. Ensure proper precautions and correct safety
measures are adhered to.
Verification
procedure
1. Enter CL50 Calibration mode.
2. Set the DMM mode to AC mV. Press Shift + ACV.
3. Input 200mV/50kHz.
4. Check the DMM display. If the voltage is within the
specification range, go to the next adjustment range. If
not, adjust variable capacitor VC305 until the voltage is
within specification.
Range: 200.50mV±10 digits
5. Set the DMM to ACV mode, 5V range.
6. Input 4.9V/10kHz.
7. Check the DMM display. If the voltage is within the
specification range, go to the next adjustment range. If
not, adjust variable capacitor VC301 until the voltage is
within specification.
Range: 4.9V±10 digits
8. Press Up to set the DMM range to 50V.
9. Input 49V/10kHz.