4
Acceptance Testing
CPI Canada Inc.
Use and disclosure is subject to the restrictions on the title page of this CPI document.
Page 4-6
CMP 200
®
X-Ray Generator Service Manual Ch # 901476-06
Rev. A
4.4.0
ACCEPTANCE TESTS (kV, TIME, mA AND mAs) Cont
Step
Action
Result
Check
2.
Set up an mA / mAs meter to measure X-ray
tube current by temporarily open-circuiting the
mA measuring link E17-E18 on the HT tank.
Connect the mA / mAs meter to these
terminals, following the device manufacturers
instructions.
Connect the output of the mA / mAs meter to
channel 2 of the oscilloscope.
N/A
IF HIGH kV EXPOSURES ARE NOT ALLOWED IN THE FOLLOWING STEPS, CHECK THE MAXIMUM kV
SETTING THAT HAS BEEN PROGRAMMED. REFER TO “TUBE SELECTION” IN CHAPTER 3.
Step
Action
Result
Check
3.
Switch ON the generator and after initialization
select the following parameters:
kV = 100, mA = 100, time = 50 ms.
N/A
4.
Make an exposure and verify the following
results.
kV = 100 kV
±
3%.
mA = 100 mA
±
5%.
Time = 50 ms
±
2 ms.
5.
Repeat step 4 but set the values to
kV = 65, mA = 200.
kV = 65 kV
±
3%.
mA = 200 mA
±
5%.
Time = 50 ms
±
2 ms.
6.
Repeat step 4 but set the values to
kV = 125, mA = 200.
kV = 125 kV
±
3%.
mA = 200 mA
±
4%).
Time = 50 ms
±
2 ms.
7.
Select 75 kV, 200 mA.
Select the exposure times shown below (3
point operation).
Measure time and mA on the ‘scope and
check that their product is as per the RESULT
column.
Measure time at 75% of the peak kV
waveform.
A: 10 ms (2 mAs)
B: 20 ms (4 mAs)
C: 63 ms (12 mAs)
D: 100
ms
(20 mAs)
A: 2 mAs
±
5%.
B: 4 mAs
±
5%.
C: 12 mAs
±
5%.
D: 20 mAs
±
5%.