CT – Current Transformer & PT – Potential Transformer are measuring devices in AC system. These are also called as instrument transformers. As AC system deals with very high power hence we require Ammeter & voltmeter of humongous sizes to measure such high power which is impractical & expensive too.
CT has following properties:-
- it is a intensify transformer.
- It enhances the voltage & thus this gets reduced for a tough and fast power, since P= V×I×cosΦ. Thus for a tough and fast amount of power, current can easily be measured.
- primary winding of a CT is typically connected serial with the load & secondary winding is connected with the ammeter.
About Electrical House Wiring
PT has following properties:-
- it’s step down transformer.
- It reduces the voltage for a tough and fast power & thus the voltage can easily be measured, since P= V×I×cosΦ
- the primary winding of the PT is typically connected in parallel to the load & secondary winding is connected to the voltmeter.
- CT- Current transformer
- PT- Potential transformer
CT and PT form the sub parts of instrument transformer .They are extensively utilized in power system for metering and protection purpose .These 2 form the foremost important a neighborhood of any substation .Since in actual electrical power system we affect high voltage and high current and it isn’t feasible and economical to manufacture devices to measure such high values .So to measure high values in power system use CT and PT. the primary of those transformer is placed in path and secondary is placed in any meter or relay relying on the appliance . The turns of primary and secondary are adjusted in such a fashion that this in secondary is small and easy to measure for CT and voltage just just in case of PT .Also they provide isolation between primary and secondary which is typically required in electrical.