1) Switch on power source switch, indicated light not on.

Reasons: a. power source switch broken.

       　　b. fuse ACFU fusing.

2)  Switch on power source switch, indicated light on, but not outputting ultrasonic.

Reasons: a. transducer and ultrasonic power board conneting abnormally.

      　　 b. fuse ACFU fusing.

      　　 c. ultrasonic power generator broken.

      　　 d. transducer broken.

3) Direct current fuse DCFU fusing.

Reasons: a. commutate bridge or power tube burnt down.

       　　b. transducer broken.

4) Switch on power source, outputting ultrasonic, but cleaning result not good.

Reasons: a. position of cleaning liquid in cleaning trough incorrect.

     　　  b. ultrasonic frequency adjusting incorrectly.

     　　  c. temperature of liquid in cleaning trough too high.

     　　  d. wrong cleaning liquid.