Planmeca Proline EC ceph, Техническое руководство

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Chapter F - PREVENTIVE MAINTENANCE
F-6 Planmeca Proline EC X-ray unit
MECHANICAL CHECKS
Technical Manual
Exposure time measurement
A calibrated oscilloscope is needed for invasive exposure time measurement. Connect oscil-
loscope channel 1 to the Generator CPU board’s connector P18:10 and oscilloscope ground
to the Generator CPU board’s connector P4:2 (GND). The exposure time can be defined from
the oscilloscope screen as the time interval during which the tube potential exceeds 70% of
the peak tube potential. The exposure time must be within ±10% of the value displayed in the
user interface.
Feedback signal offset measurement
The KVM-feedback signals have a small offset voltage that is used for internal self-testing of
the equipment. In some cases, it can be useful to measure these offsets for troubleshooting
purposes etc. The offset of all feedback signals should be 277 ± 30 mV with respect to the
unit ground potential. The offsets should be measured in idle state (before exposure).
3 MECHANICAL CHECKS
Refer to the chapter “ADJUSTMENT & CALIBRATION” on page D-1.