Exposure Time Verification - Sirona Orthophos 3 Maintenance Manual

Sirona Dental Systems GmbH

Exposure Time Verification

• The pulse counter is still connected as described on previous page.
1. Prepare unit for tele-exposure:
Adjust diaphragm 3 for tele-exposure on the diaphragm wheel.
Swing panorama cassette holder out of x-rax path.
Press R key to move x-ray head into position for tele-exposure.
For details see Operating Instructions for Tele-Exposures, chapter "Preparing the Tele-Exposure"
2.1 At the Multitimer select 72kV/10mA and 1.0 second.
• Make four exposures CAUTION RADIATION !
Depress the exposure key and hold depressed until the exposure terminates automatically.
- Record pulse count and reset pulse counter after each exposure.
1. exposure ......................... pulses
2. exposure ......................... pulses
3. exposure ......................... pulses
4. exposure ......................... pulses
total ................................. pulses, divided by 4=
- - Record average pulse count.
At 60Hz: nominal 1.0 sec. = 60 pulses±2
2.2 At the Multitimer select 72kV/10mA and 2.0 seconds.
• Make four more exposures CAUTION RADIATION !
Depress the exposure key and hold depressed until the exposure terminates automatically.
- Record pulse count and reset pulse counter after each exposure.
1. exposure .........................pulses
2. exposure .........................pulses
3. exposure .........................pulses
4. exposure .........................pulses
total .................................pulses, divided by 4=
- - Record average pulse count.
At 60Hz: nominal 2.0 sec.=120 pulses±2
3. If specified values are obtained, switch unit OFF.
Remove meter leads and refit small metal cover (2 screws).
• If specified values cannot be obtained, see Service Manual, chapter "Exposure Time Verification".
59 01 603 D3285
D3285.103.04.02.02
for Tele – Exposure
Allow a 5 mins. cool-off time between exposures!
(automatic exposure blocage)
average pulse count.
at 50Hz: nominal 1.0 sec. = 50 pulses±2
Allow a 5 mins. cool-off time between exposures!
(automatic exposure blocage)
average pulse count.
at 50Hz: nominal 2 sec.=100 pulses±2
Maintenance Instructions
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