The CT machine's high-voltage generator for Micromatic (referred to as MMCT) is Siemens CT machine use more common high-frequency high-voltage generator, Generator ok signal that (GEOK) is in the rotation on (AVO), filament on (HU) signal arrives, the computer (CPU) to send an exposure signal, the exposure to observe AVO, HU yellow indicator light is on for a moment, and then go out indicates that these two signals are there because there is no detection of GEOK signal, the inverter does not work and does not produce. Exposure to observe the AVO, HU yellow indicator light on a little bit on the extinction of the two signals is there, because there is no detection of the GEOK signal, the inverter does not work and did not produce rays. PT 510 tester were used to do 60Hz rotating anode, filament temperature increase, adjust the transformer and other tests, found that the bulb filament temperature increase did not pass (Heating notok), in the TSO detection program to do Generator (GEN) test pulse exposure are normal, but do air correction (CAL) or loaded with a patient mode (MOD) to do the scanning will appear! CN0060 fault, so you can be sure that the high-voltage control part should not be a problem, so focus on analyzing and checking the filament warming circuit, consider the bulb tube use longer, the filament may be aging, so appropriate to increase the filament voltage, the filament power supply transformer (T501) of the primary voltage jumper from the 50V file changed to a 70V file, the measurement of the actual voltage rose from 45V to 60V, test was found to be Heating ok, but can not be exposed, it can be concluded that the filament does have aging, 70V file voltage may be too high beyond its range, so find a way to slightly increase the voltage on the basis of the 50V file voltage, but only 50V, 70V, 80V file adjustable on the TS01, through the analysis of the schematic diagram found that the entire high-voltage cabinet input power supply can be jumpered to determine the number of input voltages, measurement of the machine Input voltage of 402V AC, and the original installation of the choice of jumper in 420V, change the jumper to 400V gear, measuring the filament primary transformer voltage of 46V, slightly larger than before the change, the original 45V, but still can not be normal exposure, and then jump to the 380V gear, the filament voltage of the primary for the 46.9V, this time you can be exposed, and the scanning is normal, and the quality of the image can also be.
CT machine maintenance summary: this fault is more special, originally thought it was a bad bulb, ready to replace, after careful testing and analysis, to determine the bulb filament aging, but can be used, so in the replacement of large or expensive parts should be careful.