Failure repair of electronic balance shared by Analytical Balance Supplier.
8. Bad judgment of sensor
Resistance method: first test whether the resistance between E+E- and S+S- is close to its nominal value. If normal, you can also measure the resistance between E+S+ and E+S-, which should usually be the same or close (the difference is more than 2 ohms and basically there is something wrong with the sensor).
The resistance method is usually difficult to determine the sensor damage (only serious damage, the resistance value will change), so a more direct method is the voltage method, the sensor E+E- connected back to the substrate, disconnect S+S-, S+S- to 10,000 millivolts. Of course, the premise is that E+E- power supply is normal, if the 5V voltage between E+E- is abnormal, you can also disconnect, and then directly connect to E+E- with a battery. Then we measured the voltage between S+S- under no load and full load respectively. Theoretical sensor output voltage = excitation voltage X sensitivity X (current load/sensor range) + zero output.
9. Angle deviation
If you find the deviation of four corners, please do not hurry to adjust the junction box or cut the four corners, especially the very serious Angle difference. Once it is misoperated, it is difficult to recover. First, we should exclude the possibility of weight table and sensor touching foreign objects, and then we should consider the contact problem of sensor wiring (if it is the loadometer of four sensors). If abnormal conditions are excluded, then we can only cut four corners. First of all, it should be emphasized that the correct way to measure the four corners is to place the 1/3 full range weight in the center of the four evenly divided regions or lay it flat in the region, not on the most edge of the four corners. File corners, to file the other side of the mill scale values in the corners of the lowest according to the zero test again after four corners, mill scale for the first time, please try with a small force grinding ways to test their strength, to avoid the sensor damage, and repeat the file a to examine a file a measured again, until the scale the four differences within the scope of the positive and negative a word, to do the weight correction. Note: be careful when filing the corners of the sensor with small measuring range. For the four sensor loadometer, it is to adjust the junction box, usually rotating in time to increase the reading, also recommended from the reading of the smallest Angle.
10. sensor compensation
If the zero position of the sensor is too high, add resistance between E+S-; if the zero position of the sensor is too low, add resistance between e-s -, and the resistance value can be between 50K and 10M. The smaller the resistance value, the greater the impact on the zero point. Use high precision low temperature resistance whenever possible. Note that this is only a temporary solution. After using this method, please recalibrate the electronic scale and replace the sensor in time to completely solve the problem.
That's all for the sharing, thanks for your reading, and we also supply 0.01g electronic laboratory scales for sale, if you have any demand for our products, just feel free to contact us.