Abstract：In this paper, a case of UDRS with occasional EXQ2 interlocking failure occurring in varian Trilogy linear
accelerator in our hospital was summarized, including its causes, investigation and maintenance results. According to the low
dose rate fault performance and the working principle of accelerator, firstly, the characteristic waveforms of RF, injection and
AFC systems were examined successively according to the low target current, and the general direction of fault was judged to
be between the accelerator tube and the X-ray target. The deflection coil and several groups of coils acting on the accelerator
tube were examined, and the current of the bunching coil was found to be low. Finally, the bunch-coil circuit was checked to
confirm that the fault was caused by the circuit change caused by the welding spot problem of precision potentiometer R11 on
the energy programming board. The quality control of the equipment after troubleshooting is an important step to ensure the
delivery and clinical use of the equipment.
宁波市第一医院 放化疗中心，浙江 宁波 310510. 瓦里安Trilogy型直线加速器UDRS伴偶发EXQ2联锁故障维修一例[J]. 中国医疗设备, 2019, 34(10): 180-182.
YANG Jiming, REN Jiangping. One Case of Varian Trilogy Linear Accelerator UDRS with Occasional EXQ2 Interlock
Troubleshooting. China Medical Devices, 2019, 34(10): 180-182.
