Service Manual
Service Instructions
Siemens Ltd. Med India
Version 6.0
Copyright
SIEMENS LTD. All rights reserved. For internal use only
7-9
7.13 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 = 20mA & 1V=20kV) for selected kV & mAs .
7.14 Checking the mAs values
Turn the Unit OFF.
Remove the Shorting Link “mAs +/-” on D920 PCB banana sockets.
Connect mAs meter to “mAs +/ mAs-” on D920 PCB.
Turn the Unit ON.
Trigger the following exposures:
Setting at control panel
Valid mAs values
40kV,200 mAs
190..210 mAs
66kV,100mAs
95...105 mAs
90kV,1mAs
0.9.....1.1mAs
Turn the Unit OFF.
Remove the mAs meter and reinsert the Link on the D920 PCB.
7.15 Adjusting the mAs
Turn the Unit OFF.
Remove the Shorting Link “mAs +/-” on D920 PCB banana sockets.
Connect mAs meter to “mAs +/ mAs-” on D920 PCB.
Turn the unit ON.
Trigger the exposures for default kv & mAs settings.
Observe the mAs meter reading and if it is not within the tolerance (specified in the
Technical Specifications) of set value adjust the P1 on D915 card
7.16 Switching the Collimator Light ON
Switch ON Collimator Lamp. The Halogen lamp will light up and field of light will appear
on the target. The lamp will be switched OFF automatically after 30 seconds.
If the collimator lamp is switched ON and OFF several times within a short
period, overload protection will automatically switch the light OFF. Cool-down periods
are recommended.
7.17 Program Modes for servicing.
To put the Unit into service Mode short the ST link on the D915 and turn ON the unit
.The display will show as follows
P r
1
