BCH-2 Differential relay

Technical data

1. Rated current 5A, rated frequency 50Hz.
2. The initial ampere turns of the relay is 60+4.
3. Dc magnetic characteristic curve of the relay 9(As shown in FIG. 3)∈=f(K) for subsection adjustment;
The ratio of the K-DC component to the corresponding AC action value.
∈- the ratio between the ac operating current of a relay with a DC component and the ac operating current without a DC component.
FIG. 3 shows a ∈= F (K) curve cluster when the short winding is connected with different turns. When K=0.6, corresponding to each short circuit coil tap,∈ values according to the following provisions:
Short-circuit winding extraction and research location: ∈ : a-A, 1.6+0.13;B - B, 3 + 0.24;C - C, 5 + 0.38;D - D, 7 + 0.56;
4. The reliability coefficient shall be no less than 1.35. The reliability coefficient shall be determined according to the following method: set the operation current of the relay as Id, and the operation current of the corresponding actuator dL-11 relay as I1;Then turn the pointer and tighten the hairspring, so that the action current of the differential relay is 5Id, and then measure the corresponding action current i5 of the actuator, and calculate the reliability coefficient according to the following calculation:
Kk= i5/i1
5. When the operating current is 3 times, the operating time of the differential relay shall not be greater than 0.035s.
6. When the voltage does not exceed 220V and the current does not exceed 2A, the relay contact disconnect capacity is 50W in the DC inductive load (time constant is 5x10s) circuit.
7. At the rated current, when the balance winding (I or II) and the turns of the working winding of the relay are all connected, the single-phase power consumption of the relay shall not be greater than 16VA.
8. When the surrounding medium temperature is +40℃, the working winding and one balance winding of the relay shall be able to pass 10A current for a long time, and the temperature rise shall not exceed 65℃.
9. Dielectric strength: each circuit of the relay shall withstand 50Hz, 2kV AC voltage for 1min between exposed non-charged metal parts without breakdown or flashover.
10. When the turns of each winding are all connected and the short-circuit winding is connected at a-A position, their impedance values are shown in Table 1.

Table 1

11.The winding data of relay are shown in Table 2

Table 2

The outline and hole size of the relay are shown in FIG. 1