In the complex electrical system of a thermal power plant, the reliable operation of the equipment is crucial. As an important electrical control component, the CZO-100/20 contactor plays an indispensable role in equipment protection. It ensures the safe and stable operation of many equipment in a thermal power plant through a variety of functional mechanisms, reduces the frequency and impact range of faults, and improves the production efficiency and safety of the entire power plant.

1. Review of the basic functions and working principles of contactors

(I) Basic functions

The contactor mainly has functions such as control circuit switching, protection circuit, signal conversion and delay control. These functions are well reflected in the CZO-100/20 contactor.

(II) Working principle

The contactor uses the current flowing through the coil to generate a magnetic field to close or open the contacts, thereby controlling the load. For the CZO-100/20 contactor, it can accurately control its own on-off action according to external control signals (such as switch buttons, control signals or automatic control systems).

2. The specific significance of CZO-100/20 contactor in equipment protection of thermal power plants

(I) Circuit protection

1. Overload protection

• In thermal power plants, many electrical equipment (such as motors, etc.) may be overloaded during operation due to load changes and other reasons. CZO-100/20 contactors have overload protection functions. When the current of the controlled equipment exceeds its set rated current, the overload protection device inside the contactor will quickly sense and issue an action command.

• For example, in the auxiliary motor of the generator set, if the load suddenly increases due to mechanical failure, the current will increase accordingly. CZO-100/20 contactors can cut off the power supply in time to prevent the motor from being damaged by overheating. This can avoid further damage to the equipment and reduce maintenance costs. It can also prevent chain reactions caused by single equipment failures and ensure the normal operation of the entire power generation process.

2. Short circuit protection

• Short circuit is an extremely dangerous electrical fault that may occur in the electrical lines of thermal power plants due to insulation damage and other reasons. Once a short circuit occurs, the current will increase sharply in an instant.

• The short-circuit protection function of the CZO-100/20 contactor can quickly detect this abnormal current increase and immediately cut off the circuit. This is like quickly turning off the switch when a danger occurs, preventing the short-circuit current from causing serious burning damage to the equipment and protecting various electrical equipment in the power plant, such as transformers, switch cabinets, etc. from the impact of short-circuit current.

(II) Multi-channel control and equipment interlock protection

1. Multi-channel control

• There are a large number of equipment in thermal power plants that need to work together. The CZO-100/20 contactor can realize the linkage control of multiple equipment in an electrical control system.

• For example, in the coal feeding system, air supply system and induced draft system of the boiler, the coordinated operation of these systems can be achieved through the reasonable connection and control of multiple CZO-100/20 contactors. When one of the systems fails, the operation status of other systems can be adjusted through the action of the contactor to improve the reliability and stability of the entire system.

2. Equipment interlock protection

• When there are interrelated and restrictive relationships between some equipment, the CZO-100/20 contactor can realize the interlock protection of the equipment by controlling different contacts.

• For example, during the startup of the generator set, when the lubricating oil pump has not started normally and established sufficient oil pressure, the interlocking function of the contactor can prevent the main engine from starting. This can avoid serious wear and even damage to the main engine equipment due to lack of lubricating oil, and ensure that the equipment operates in the correct order and safe conditions.

(III) Fault signal transmission

When the controlled equipment fails, the CZO-100/20 contactor can automatically cut off the power supply and output a fault signal.

• In the monitoring system of the thermal power plant, this fault signal can be detected in time. For example, in the motor control circuit of the steam turbine, if the winding of the motor fails, the contactor cuts off the power supply and sends a fault signal. The staff of the power plant can quickly locate the fault point according to the signal and take corresponding maintenance measures. This helps to troubleshoot in time, reduce downtime, and improve the reliability of equipment and the power generation efficiency of the entire power plant.

(IV) Application of delay control function

In some cases, the delay function of CZO-100/20 contactor is also very important for equipment protection.

• For example, during the shutdown process of the generator set, all control and protection power supplies cannot be cut off immediately. By setting the delay time of the contactor, some auxiliary equipment (such as cooling system) can continue to run for a period of time after the main engine stops running to ensure the normal cooling of the equipment and prevent overheating damage to the equipment due to sudden stop.

CZO-100/20 contactor has many meanings in the protection of thermal power plant equipment. It ensures the safe and stable operation of many electrical equipment in thermal power plants through multiple functions such as overload, short circuit, interlocking protection, fault signal transmission and delay control. Power plant engineers should pay full attention to these protection significances of CZO-100/20 contactor in the process of equipment selection, maintenance and management to ensure the efficient and safe operation of thermal power plants.

When looking for high-quality, reliable electric contactors, YOYIK is undoubtedly a choice worth considering. The company specializes in providing a variety of power equipment including steam turbine accessories, and has won wide acclaim for its high-quality products and services. For more information or inquiries, please contact the customer service below:

E-mail: sales@yoyik.com
Tel: +86-838-2226655
Whatsapp: +86-13618105229