How to use a multimeter to repair an ultrasonic cleaner
1. There is no ultrasound, the indicator light of the power switch has no display, and the fan is running normally. ①. Check whether the rectifier bridge is damaged.
The method is: adjust the pointer multimeter to the ×10k position, connect the black test lead to the positive pole of the rectifier bridge, and connect the red test lead to the ac terminal to see if the two pins are connected, and if so, check the next step.
②. Check whether the main capacitor is damaged, and if so, replace the battery.
③. Check whether the power tube is damaged.
The method is: set the pointer multimeter to the ×10k gear, connect the black test lead to pin 2 of the power tube, and connect the red test lead to pin 1 and pin 3 to see if it is connected, if yes, replace the power tube, otherwise restore the working state.
2. There is no ultrasound, the indicator light of the power switch is off, and the fan does not turn.
① Check whether the power switch is damaged, if yes, replace the power switch, otherwise check the next step.
②Check whether the fan is damaged, if so, replace the fan.
3. There is no ultrasound, the indicator light of the power switch is on, and the fan is running normally.
①Remove the output cable, turn on the power, adjust the power to the maximum, use a multimeter to measure the voltage at the output terminal at 1000v, generally around 1000v, if there is voltage, it means that there is no problem with the generator, plug in the output cable, and check the first Step ⑤, if there is no voltage, check the next step.
② Use a multimeter with a DC 1000v gear to measure the positive and negative ends of the main capacitor or the output of the rectifier bridge. If there is about 300v, check step ④ if there is no voltage, and check the next step if there is voltage.
③Use a multimeter to measure the frequency of d1 at 20v, and the diode should be around 10v. If there is no voltage, replace the IC1 module.
④ Check the power control part, measure whether the power adjustment potentiometer is short-circuited, and if so, replace it.
Otherwise, check the power. The control output resistor r3 should be 240 ohms. If the 5w resistor is damaged, replace it.
⑤ Check whether the ultrasonic vibrator is normal. You can use a megohmmeter to measure the insulation resistance at both ends of the vibrator, which is generally more than 500k or use the x10k block of a multimeter to measure the resistance at both ends of the vibrator. Generally, the needle will swing slightly and return to its original position , Replacing the test leads will have the same effect. If the resistance is too small, it may be a problem with the vibrator, and it will be short-circuited after being damp.
4. There is ultrasound, but the power cannot be adjusted.
① Check whether the thyristor is short-circuited, replace it if yes, otherwise check the next step.
② Check whether the triode t5 is damaged, and if so, replace it.
5. The intensity of ultrasound becomes weaker.
①Use a frequency meter to measure whether the main engine is within the normal frequency range. Generally, the vibrator of 28k is 27-31k, and the vibrator of 40k is 39-41k. If the difference is too large, it can be restored by adjusting the frequency adjustment potentiometer on the main board.
②Observe the current of the ammeter. If the current is too small than the rated current, first check whether the ultrasonic vibration plate is damaged, such as the vibrator falls off, the vibrator chip is broken, the bonding glue is cracked, etc., and whether the connecting wire is short-circuited.
Under normal circumstances, if the current drop is not much or basically does not drop, and the sound is normal, but the ultrasonic intensity drops sharply, it is likely that the bonding glue of the vibrator is cracked. The judgment method is: observe the connection between the vibrator and the steel. The glue coating should be a smooth surface under normal circumstances. If there are small cracks, it is likely that the glue has cracked. At this time, the vibrator should be removed and rebonded. If the current drops sharply, it is mainly to check whether there is a disconnection of the connecting wire. Or the vibrator chip is broken.
③The general working voltage, cleaning object, water temperature and the type of cleaning solution will all affect the ultrasonic strength, especially when it is violently stirred, the ultrasonic will be weakened and it will take tens of seconds to recover. The main method of use.
Simple troubleshooting of ultrasonic cleaning machine
If the transducer is damaged, the insulation strength is 0. If the transducer is damaged, 1. Use an ohmmeter to measure the insulation strength of the control board, which is greater than 5 megohms.
Unplug the positive or negative plug, the rectifier bridge is broken, 2, the air switch is broken, the module is broken, the module is broken, and the module is broken. Note:
one,
1. The first relay picks up, but the second one doesn't pick up because the control board is broken.
2. When the power-on resistor is broken, the circuit breaker also trips.
3. When the module is broken, sometimes it will not jump when it is turned on.
