KaVo ORTHOPANTOMOGAPH OP 2D, Service Manual

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4. Troubleshooting
ORTHOPANTOMOGAPH OP 2D 73
From the s2terminal, select calib and calibrate the
tubehead.
NOTICE!
Keep exposure switch pressed for the duration of the
calibration program.
After recalibrating the tubehead check if the calibration
was successful.
If the calibration is successful select the exp function
again and con fi rm that the mA and kV feedback signals
are correct.
If the calibration was unsuccessful and the unit still
does not work correctly, check the hardware.
Hardware check
Remove the cables from the tubehead side of the rotat-
ing unit. Check the cables between the Tubehead and
the Generator board. Replace them if they are faulty
and then recalibrate ( calib ) the tubehead.
If recalibration is not sucessful, measure the feedback
signals from the L1800 Generator board. From the
s2terminal select exp .
Connect a DMM to the TP14 (kVfb) and TP17 (GND) on
the Generator board and take an exposure.
Then connect the DMM to TP18 (mAfb) and TP17
(GND) and take another exposure.
The values for feedback signals can be counted as de-
scribed in chapter 3.6 L1800, Generator Board - Test
points.
If values for the feedback signals are not within the lim-
its, and recalibration does not help, measure the refer-
ence signals from L1800 Generator board.
Connect a DMM to TP12 (kVref) and TP17 (GND) on
L1800 and take an exposure.
Then connect the DMM to TP11 (mAref) and TP17
(GND) and take another exposure.
The values for feedback signals can be counted as de-
scribed in chapter 3.6 L1800, Generator Board - Test
points.
The values for the feedback signals should be within
the limits as described in the chapter 1.7 Yearly Main-
tenance .