Importance of the Primary Injection Tests!
Primary injection testing is essential in commissioning and verifying a protection scheme since the secondary injection test does not check all the components in the system and the condition of the overall protection installation; unlike the primary injection testing, the secondary injection tests do not simulate the real operating conditions, it would not reveal a defective CT, whether that CT is the correct ratio or polarity, or whether the secondary wiring is correct and serviceable.
The primary injection testing is the only way to prove correct installation and operation of the whole protection chain, as involves testing the entire circuit; current transformer primary and secondary windings, relays, trip and alarm circuits, circuit breakers and all wiring are checked. Primary injection testing is often the last test performed in the commissioning and maintenance process, or after any modification, as a functional test of the whole system, not excluding the also needed secondary injection tests that must be performed first. Primary injection testing is also a big help in troubleshooting and corrective maintenance.
The primary current flowing through the equipment is measured in the power system high-voltage power supply test, maintenance system test and current transformer test. The instrument generates a large current from the power supply to simulate the rated current or fault current in the primary circuit of the power equipment.
Primary Current Injector is essential equipment used for electrical debugging to generate high current, which be widely used in power plants, power distribution stations, electrical plants , scientific research, laboratories and other units. It is a short-term or intermittent work device and characterized by small size, light weight, good performance, easy use and maintenance.
1) The large current input flows through the main circuit of the operating line to simulate the fault current, and then it is checked whether the maintenance system can be designed according to the operator.
2) The large current input flows to the primary side of the current transformer, and then the induced current is measured by the error measuring instrument from the secondary side to detect the current transformer ratio difference and phase conversion.
3) The large current input flows through the main circuit of the high-voltage power supply to simulate the rated current of the primary side, and then the stability of the power supply is detected according to the temperature rise process as an AC large current source in power equipment or cable testing.
1. Working power supply: AC220V or AC400V, 45Hz~65Hz, the working voltage is different and the power input capacity is different.
2. Rare input current: 500A or 1000A or 2000A.
Rare input capacity: 3KVA or 5KVA or 10KVA or 15KVA.
