Published: 2026-05-11 Article source:
Hello everyone, welcome to General Measure's channel. In this video, we'll demonstrate how to troubleshoot a black screen issue on the touchscreen of a General Measure bagging scale.
In real-world applications, bagging scales are inevitably affected by external environmental factors, which may lead to some faults. In such cases, targeted troubleshooting is required for different issues.
A black screen is usually caused by three situations:
If the device is powered on normally but the screen is black, it is highly likely that the touchscreen has entered screen saver mode. Tap the screen and check whether the display is on or not. If it does, the touchscreen is under screen saver mode.
If you want to switch off this function:
Go to Parameter Settings → System Information → Page 4 → Switch off “Auto Screen Off When Idle”
If tapping the screen does not restore display but the device is powered, the wiring in the electrical control cabinet should be checked. Follow this sequence: check the main power circuit first, then the control circuit.
① Check the Main Power Circuit
First, check whether the external power supply is live and ensure that the power cables are securely connected. Then use a multimeter to measure whether the supply voltage is within the normal range (AC 220V ±10%).
For example, the measured voltage is AC 233.5V, it is within the normal range, indicating normal power supply.
Power supply abnormal:
If the voltage exceeds this range (AC 220V ±10%) or no voltage is detected, the external power supply is abnormal. Check whether external power is properly supplied.
If the external power works, proceed to check the switching power supply:
First, ensure input wiring is secure
Then, measure input voltage (normal range: AC 220V ±10%)
For example, AC 233.6V is within the normal range, indicating normal power input.
Switching power supply abnormal:
If the voltage is out of range (AC 220V ±10%) or cannot be measured, the main power circuit is faulty and requires careful inspection.
Also, observe the indicator light on the switching power supply. If it is off, the switching power supply itself is faulty and should be replaced
② Check the Control Circuit
If the main power circuit works well, check the control circuit.
First, verify that the touchscreen cable and the DC24V terminal block are securely connected. Then measure the supply voltage (DC 24V ±10%).
DC 24.11V is within the normal range, indicating normal power supply. At this point, check the wiring and voltage at the power input interface on the back of the touchscreen.
Remove the side cover of the touchscreen:
First, check whether the cable is firmly connected
Then, measure the voltage
The measured voltage is DC 24.05V (within range), the power cable is normal, and the touchscreen is likely damaged — replace the touchscreen.
If the measured voltage is outside the normal range (e.g., 0.645V), the power cable is faulty — replace the cable.
If both the touchscreen cable and DC24V terminal block show abnormal voltage (e.g., 0.708V):
Power supply abnormal:
Determine whether the issue is caused by the switching power supply or the terminal block/wiring
Next, check the switching power supply:
First, ensure wiring is secure
Then, measure output voltage
The output is DC 24.11V (normal), considering the terminal block is faulty — replace the terminal block.
If the output is abnormal (e.g., 0.500V).
Power supply abnormal:
The switching power supply output is faulty and should be replaced. If the issue persists after replacement, the terminal block may also need replacement.
Finally, if multiple bagging scales of the same model are available on-site, cross-testing components can help quickly identify the faulty part.
That's all for this video. If you'd like to learn more about other features of this product, feel free to get in touch with General Measure!