Doppler Weather Radar - METNET - India Meteorological Department

6. Wait for ten minutes. Calibrate the Filament Power Supply Inverse Voltage and meter
voltage according to meter calibration procedures No.11 No.12 as described in 6.3 of
MEHB 10-511.
Table C.1. Location and Calibration of panel meters
No. Position Parameter
1 A1P1 Filament
Current
Calibration method
Adjust PS1A1RP10 to make the reading of A1P1 equal to the filament
current value on the nameplate of klystron V1. Then, use a multi-meter
to measure TP2 of A1A2 and obtain a value X. The values Y, Z and M
are obtained from the formulas Y=(25X)/27.8, Z=32X/27.8 and
M=50X/27.8. Adjust potentiometer A1A2R8 while monitoring pin 5 of
A1A2U8 with the multi-meter and set the voltage equal to Y. Adjust
potentiometer A1A2R20 while monitoring pin 9 of A1A2U8 with the
multi-meter and set the voltage equal to Z. Adjust potentiometer
A1A2R5 while monitoring pin
13 of A1A2U8 with the multi-meter and set the voltage equal to M. With
these steps, the calibration of the Filament current protection is
completed. The over-current value of the Filament is typically 32A and
the under-current value is typically 25A.
2 A1P2 Focus Coil
Current
3 A1P3 Ion Pump
Current
4 A1P4 Charge
Voltage
Adjust PS2A1RP7 to make the reading of A1P2 equal to the focus coil
current value on the nameplate of klystron V1. Then, measure TP3 and
obtain a value X. similar to the calibration method for Filament Current
protection. Y and Z can be obtained according to the formulas Y= (20X)
/22 and Z= 24X /22. Adjust potentiometer A1A2R6 while monitoring
pin 5 of A1A2U6 with the multi-meter and set the voltage equal to Y.
Then, adjust potentiometer A1A2R7 while monitoring pin 2 of A1A2U6
with the multi-meter and set the voltage equal to Z. With these steps, the
protection circuits for Focus Coil Current are now calibrated. The overcurrent
value of Focus Coil Current is typically 24A and the undercurrent
value is typically 20A.
No calibration is necessary.
Measure the PFN Charge voltage at A12XS6 using an oscilloscope and
read the value. Adjust A1A2R3 to make the reading of A1P4 equal to
the value.
5 A1P5/
SA9-1
6 A1P5/
SA9-2
+5 VDC Adjust A1A2R27 to make the reading of A1P5 equal to 5 volts at
position 1 of A1SA9.
+15 VDC Adjust A1A2R28 to make the reading of A1P5 equal to 15 volts at
position 2 of A1SA9.
7 A1P5/ -15 VDC Adjust A1A2R29 to make the reading of A1P5 equal to 15 volts at
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