TA and TV have replaced the terms CT and PT.
TA is CT current transformer, TV is PT voltage transformer.
CT current transformer is a more precise tool for current signal measurement, meeting IEC60044-1 and VDE0414 standards.
The abbreviation of current transformer is CT, which is the abbreviation of Current transformer. The voltage transformer (Potential transformer, also referred to as PT, Voltage transformer, also referred to as VT) is similar to a transformer and is an instrument used to transform the voltage on the line.
Voltage transformer (PT), also referred to as TV and YH, is a sensor used by secondary equipment such as measuring instruments and relay protection in the power system to obtain electrical primary circuit voltage information.
Extended information
When measuring large alternating currents, it needs to be converted into a relatively uniform current to facilitate secondary instrument measurement (China stipulates that the secondary rating of current transformers is 5A or 1A).
Current transformers play the role of current conversion and electrical isolation. It is a sensor used by secondary equipment such as measuring instruments and relay protection in the power system to obtain electrical primary circuit current information. The current transformer converts high current into low current in proportion. The primary side of the current transformer is connected to the primary system, and the secondary side Connect to measuring instruments, relay protection, etc.
During normal operation, the secondary side of the transformer is in an approximate short-circuit state and the output voltage is very low. During operation, if the secondary winding is open-circuited or an abnormal current flows through the primary winding (such as lightning current, resonant overcurrent, capacitor charging current, inductor starting current, etc.), an overvoltage of thousands or even tens of thousands of volts will be generated on the secondary side. .
Baidu Encyclopedia - Current Transformer
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