1, there is no reaction at boot, the panel indicator is not bright

Such faults are generally caused by disconnection or abnormality of the power supply part of the circuit board inside the operation panel. If there is no fault inside the machine control box, it is important to check whether the connection line between the control box and the operation panel is open, and check the roots; if the connection line is intact Check whether the plug and socket are connected reliably, and whether there are any solder joints at each solder joint; if the fault persists after inspection and processing, it means that the circuit integrated block inside the panel is damaged. Because such circuit board is mostly a patch circuit, only Can replace the entire board to repair.

2, the speed regulation is abnormal

Such faults are mostly caused by poor speed regulator VR1. If the speed regulation is abnormal due to the dirty surface of the VR1 slider, please solve the following method: Disassemble the operation panel, remove the VR1 lever, wipe the semiconductor surface with a small amount of absolute alcohol with absorbent cotton, and clean the surface and keep it in contact. After the face is dried, the lever can be installed. If the speed regulation is abnormal due to severe wear of VR1 or internal disconnection, replace the entire VR1 potentiometer.

3, some function keys are invalid

There are two kinds of such faults: (1) Turn on the power switch, some function keys are disabled and the buzzer is silent; (2) Turn on the power switch, some function keys are disabled but the buzzer's button sound is normal.

The former type of fault is generally caused by the contamination of the conductive rubber in the button and the contact of the printed circuit board or the damage of the conductive rubber, which may result in the failure of the trigger pulse signal. The maintenance method is to disassemble the circuit board and check whether the conductive rubber of the faulty button is damaged or dirty at the contact with the circuit board. If the button is damaged, replace it directly. If the contact is bad, wipe the contact surface with a cotton wool with a little alcohol. The latter type of fault is generally caused by the failure of the individual pins of the CPU on the board, and can only be replaced by replacing the board.

4, the LCD display is not normal

Such faults are mostly caused by poor moisture in the display or poor contact between the keyboard circuit and the plug and socket of the display cable. If the display screen is damp, you can use the electric hair dryer to drive out the moisture; if the plug and socket are not in good contact, check the troubleshooting as follows: If the main display is faulty, please check whether the CN102 plug socket is soldered or poorly contacted, and then check each connection. If there is no disconnection, it can be processed separately; if the bottom line residual display is faulty, check whether the CN103 plug socket is soldered or poorly contacted, and then check whether the connection is disconnected or not, and handle the fault separately.