Test Of Mas Accuracy; Oscilloscope Method - Siemens MOBILETT XP Digital Installation And Startup

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Test of mAs accuracy

Requirement:
The measured mAs values must comply with the limit values specified in the tables. One
of two measuring methods can be used:
1. mAs meter method:
- mAs meter (e.g. MAS meter 8160400 with a measuring accuracy of 1% ± 1 digit)

2. Oscilloscope method:

- Storage oscilloscope with a measuring accuracy of ± 2.5%
Oscilloscope method:
•
Close the collimator.
•
Remove the top cover and place on a table or similar surface. All cables remain con-
nected.
•
Clamp the oscilloscope to the "JR" and "GND" measuring points on CPU D916.
•
Switch the MOBILETT XP Digital on and select manual operation.
•
After switching the unit on, wait for approx. 5 minutes to let it stabilize.
Example: Calculation of the mAs value
Fig. 19: mAs calculation
The mAs value can be calculated with the help of the oscilloscope display.
Surface "A" corresponds to the mAs value.
mAs = tube current x exposure time
mAs = 340 mA x 0.006 s = 2.0 mAs
MOBILETT XP Digital SPR8-230.814.30.03.02
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