Cabinet, also known as busbar voltage transformer cabinet or voltage transformer cabinet. There is usually a set of voltage transformers, a fuse, a lightning arrester, and other main electrical components installed inside. The fuse of the fuse provides protection for the voltage transformer. Voltage transformer is a device that converts high voltage into low voltage proportionally according to a certain transformation ratio, making it suitable for the voltage requirements of the instrument.
The lightning arrester mainly serves as overvoltage and lightning protection.
The voltage transformer cabinet generally adopts a combined structure, and we can configure different types and quantities of PT according to the specific design parameters of the project.
The overall structure of the cabinet adopts a detachable metal armor structure, and the equipment panel usually has a large area of observation ports. It can observe the operation of the PT cabinet at any time. Each PT is equipped with a carriage, and its primary and secondary circuits adopt a tap structure to achieve separation of the primary and secondary compartments. The overall appearance and reliability of the cabinet can achieve on-site extraction and maintenance.
Function of PT cabinet
(1) Provide measurement voltage, instrument voltage, and protection voltage in the electrical system.
(2) Provide measurement voltage for the power meter.
(3) It can provide operation and control power (PT) for relevant equipment.
(4) Meet the needs of electrical system relay protection. Bus insulation, undervoltage, overvoltage, backup equipment self switching conditions, etc. The voltage small busbar on the top of the high-voltage cabinet screen is powered by the PT cabinet.
There are measuring PT and measuring PT in the cabinet (the original requirement was to separate the measuring PT and measuring PT, but if there are no special requirements, they can be left separate and can be shared). The small busbar at the top can be used to provide power to other high-voltage cabinets. Simultaneously providing power supply for other equipment to meet the voltage requirements for measurement, metering, and protection power supply.
The difference between PT cabinet and metering cabinet
Cabinet is a voltage transformer cabinet (PT stands for voltage transformer), usually used to install voltage transformers connected to the busbar. This voltage transformer can be used for measurement and protection.
In order to accurately measure and effectively manage various users, the power department will set up a dedicated measuring cabinet on the user side, which is equipped with voltage transformers, current transformers, and measuring instruments. The data in this table is used for the settlement of electricity bills. The management authority of the measuring cabinet is the power department, and users have no right to carry out maintenance and debugging work.