Generally, there is a synchronous camera on gravure press. The camera lamp tube is controlled by a computer. With the synchronous flash of the camera lamp, the camera synchronously captures the printed product pattern, and displays it through the display, so that the operator can observe the situation of the product at any time and adjust it in time. Taking the synchronous camera of German flfe company equipped on the imported gravure press as an example, this paper expounds the troubleshooting methods and maintenance skills of synchronous camera, for reference only.
Fault 1 inter turn short circuit of oscillation step up transformer
Phenomenon: the camera lamp does not flash.
It is found that the synchronous trigger pulse of microcomputer is available, but there is no voltage at both ends of the flash lamp. Check the circuit board, its transformer has been burned. It is found that the current of the secondary old V power supply of the transformer changes greatly. It is suspected that the inter turn short circuit of the oscillation step-up transformer causes the original transformer to burn down. Through detection, it is a short circuit in one winding of the oscillation step-up transformer. After rewinding, troubleshooting.
Fault 2 there is something wrong with the flash trigger circuit
Phenomenon: the camera flash does not flash.
First, the synchronous trigger pulse sent by the microcomputer is detected, and the result is normal. Then manually test the button, the flash can flash normally, indicating that there is something wrong with the flash trigger circuit. After checking the circuit board, it is found that the control of the triode mpsa64 is abnormal, which is PNP Darlington composite tube. Two PNP tubes c9012 were used to compound, and the trouble was eliminated.
Fault 3: the self-test of microcomputer is abnormal
Phenomenon: the self-test is not normal after the microcomputer is turned on, and the flash lamp of the camera does not flash.
First of all, it is found that the internal CMOS program and peripheral program are normal, so it is suspected that the internal display card is damaged. After replacing the display card, the microcomputer works normally, the synchronous trigger pulse is normal, and the flash can also be triggered synchronously. However, there is no product pattern printed on the display, and the screen is black, so it is suspected that there is something wrong with the camera. After inspection, the camera peripheral power supply is normal, the problem may be in the internal power supply. Turn on the camera, and sure enough, there is a large power supply integrated block damaged, unable to repair or replace. After checking the internal circuit, consulting the data, and adding a power supply, the camera returned to normal operation.