Analysis of Sensor Damage in Temperature Measurement Cable of Steel Silo
Analytical Engineer: Liu Yuliang
In steel silos, there must be electrical equipment for ventilation, temperature regulation and grain transportation. Most of these equipment will be driven by frequency converters. Inverter has great interference to power supply. According to description: 18B20 cable is dense (1.5 meters apart), and the line must be a single branch structure, the elongated wire can be seen as an antenna to collect radiation energy. In this way, the interference of the frequency converter from the power supply and the voltage induced by the cable itself can cause high voltage on the cable and cause damage. According to these two considerations, one is to strengthen power filter at 18B20 power supply terminal to reduce power interference. There is also the use of shielded cables, shielded layer connected to the granary for grounding treatment. The shield grounding point should be separated from the high-power grounding point such as frequency converter. If it is in the same electric box, it is suggested that the two grounding points should be separated by 1031KV capacitor directly. When installing, keep away from other high-power equipment as far as possible.