Aec Board Remova Land Installation; Tube Conditioning / Seasoning - CPI CMP 200 Series Service Manual

CPI Canada Inc.
6.8.0 AEC BOARD REMOVAL AND INSTALLATION
1. Switch the generator OFF at the console, and disconnect the mains voltage.
2. Disconnect the AEC chamber connections at the AEC board.
3. Disconnect the AEC control cable at J7 on the generator control board.
4. Locate the four nylon standoffs that secure the AEC board to the control board.
5. Turn the head of each plunger on the nylon standoffs approximately 90° counterclockwise.
6. Gently lift the AEC board off the nylon standoffs. Set the AEC board aside until the required
components underneath are replaced. The AEC board should only be placed on a static-safe surface.
7. Reverse the above steps to replace the AEC board.
6.9.0

TUBE CONDITIONING / SEASONING

Tube conditioning or "seasoning" is particularly important for new tubes or tubes that have not been used for
several days. This should be performed on each X-ray tube before attempting auto calibration, as an
unseasoned tube may not operate properly at higher kV values without arcing. Refer to the X-ray tube
manufacturer's instructions, if available, for the tube conditioning or "seasoning" procedure. If the X-ray tube
manufacturers instructions are not available, the following procedure may be used:
6.9.1 Tube Conditioning
The generator does X-ray tube auto calibration at 40 kV, 50 kV, 60 kV, 70 kV, 80 kV, 100 kV and 120 kV. The
tube normally needs to be seasoned before it can be operated at the higher voltages encountered during auto
calibration.
Tube seasoning is started by auto calibrating the kV stations up to and including part of the 70 kV
station. The tube is then seasoned at 70 kV. Progressively higher kV stations are then auto calibrated and
seasoned. Finally the entire kV and mA range is auto calibrated, then the tube is seasoned at the remaining
high kV values.
Manually releasing the exposure button during auto calibration of a particular kV station in the
following procedure prevents the generator from attempting operation beyond that kV/mA value.
NOTE: THE TUBE MANUFACTURER'S RECOMMENDED SEASONING PROCEDURE, IF AVAILABLE,
MUST ALWAYS BE USED IN PLACE OF THE FOLLOWING PROCEDURE.
X-ray tubes that have not been used for more than 8 hours may suffer thermal shock if operated at
high mA and kV without a warm-up procedure. A cold anode (Molybdenum) is very brittle and when
suddenly heated over a small area may experience thermal cracking of the anode surface, eventually
leading to permanent tube damage.
The procedure below is intended for seasoning an X-ray tube prior to attempting tube auto calibration. To
season a tube that does not need to be calibrated, follow steps 2, 4, and 6.
X-ray tube seasoning should be done on LARGE focus in order to minimize tube wear.
1. Start the tube auto calibration sequence, and manually terminate the exposure at 70 kV and 250 mA.
Use and disclosure is subject to the restrictions on the title page of this CPI document.
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CMP 200 X-Ray Generator Service Manual Ch # 901476-08 Rev. B
Regular Maintenance
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