FBM212 Foxboro FOXBORO Controller, Shanghai Sijian Intelligent Technology Co., Ltd. is engaged in technical development, technical consultation, technical transfer in the fields of intelligent technology, information technology, and automation technology, as well as the sales of electrical equipment, automation equipment, electronic products, communication products, and electromechanical products. Industrial automation products include: PLC, DCS, sensors, frequency converters, encoders, relays, servo drives, soft starters, touch screens. Brands involved in the products include: Eurotherm, Schneider, Siemens, ABB, SICK, P+F, E+H, Yokogawa, Yamakawa, Mitsubishi, Emerson, Honeywell, FANUC, GE, Eaton Electrical, CT.
FBM212 Foxboro FOXBORO Controller, although the methods of attacks on industrial control systems differ significantly from those on traditional internet systems, the deployment of industrial control systems is closely coupled with their physical processes. Therefore, exploiting code logic flaws in the processes has become one of the effective attack methods against industrial control systems, and such new malicious code possesses stronger propagation capabilities and destructiveness. This paper primarily studies software-based PLC code flaws and classifies PLC code flaws from two aspects: code logic defects and violations of security requirement specifications.
Soft starter faults can generally be categorized as follows:
1. Motor fails to start:
The reasons for a motor failing to start can be broadly divided into two situations:
First, one of the six thyristors has unreliable triggering or fails to conduct. In this case, one phase of the circuit passes a half-wave DC current, and the two-phase windings of the motor are subjected to DC current, which acts as a brake on the motor. Not only will the motor fail to start, but in severe cases, it may also burn out the motor and the thyristor.
Second, the motor fails to start due to inappropriate starting parameters or an unsuitable starting curve. This is a common fault. The former may occur during use, but its probability is lower than the failure rate of contactors. The latter mostly occurs during initial commissioning and debugging and will not happen again once properly adjusted. Most manufacturers do not experience this issue, as their starting programs perform well and the factory default settings are highly adaptable. Only a few manufacturers' products require debugging by the manufacturer themselves.
2. Thyristor burnout:
Thyristor breakdown or burnout. This type of fault is not limited to domestic or international brands and varies by manufacturer, but the failure rate is generally lower than that of contactors. The main issue often lies in the installation process of disc-type thyristors.