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Service Manual
Service Instructions
Siemens Ltd. Med Division India
Version 4.0
Page 21 of 48
Observe the voltage on C.R.O with the scale corresponding to 1V= 30kVfor KVS
and 1V=20KV for KV.
3.8
Setting the Maximum filament frequency
Turn the Unit OFF.
Remove the cable Connector X11 ON D915.
Connect oscilloscope to D915.TP.CAL
Turn the unit ON
The display indicates
Using P3, set the maximum filament frequency on D915 (15 kHz
±
0.5kHz)
Note: Duty Cycle of the waveform is varying as the ON time is fixed.
Connect X11 on D915.
3.9
Checking the tube current
Connect oscilloscope to D915.TP.JRS & D915.TP.JR
Turn the unit ON.
Trigger an exposure with the default values.
Observe the voltage on CRO (1V = 50mA) & confirm value for selected kV & mAs.
3.10 Checking the kV and tube current (JR)
Connect oscilloscope to D915.TP.KV & D915.TP.JR
Turn the unit ON.
Trigger an exposure with the default values.
Observe the voltage on CRO (1V = 50mA & 1V=20kV) for selected kV & mAs .
3.11 Checking the mAs values
Turn the Unit OFF.
Connect mAs meter to “mAs +/ mAs-” on D800 PCB.
Turn the Unit ON.
Trigger the following exposures:
Setting at control panel
Valid mAs values
60kV,16mAs
15.5
−
16.5 mAs
60kV,100mAs
96
−
104 mAs
100kV,50mAs
48
−
52 mAs