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High Voltage Schering Bridge

High Voltage Schering Bridge

The High Voltage  Schering bridge one in every of the most normally used AC bridge. The Schering bridge works on the principle of Equal the load on its arm.
High Voltage Schering Bridge

Fig. 1 shows where the specimen has been represented by a parallel combination of Rp and Cp.

Let, C1 – capacitor Which capacitance is to be determined,
r1 – a series of resistance, Indicate the loss of the capacitor C1.
C2 – a standard capacitor
R3 – a non-inductive resistance
C4 – a variable capacitor.
R4 – a variable non-inductive resistance

At balance condition

Z1/Z2 = Z3/Z4
Z1Z4 = Z2Z3

Schering Bridge is also Used To Measure

Applications Are capacity and dielectric, loss measurement of all kinds of capacitances, for instance, cables, insulators, and liquid insulating materials.

Dissipation Factor in Schering Bridge

The dissipation factor of a capacitor is that the ratio of its resistance to its capacitive reactance. The Schering Bridge is essentially a four-arm AC bridge and its measurement idea is predicated on balancing the hundreds on its arms.

  D1 = 2π x 50 x 3180 x C4 = C4 X 10

Since C4 is a variable decade capacitance box, it's setting in μF directly gives the value of the dissipation factor. 

Why bridge is used for the measurement of small capacitance

It is suitable for the measurement of small capacitance equipment. as the bridge uses either high voltage or high-frequency provide. If measurements for such low capacity equipment is carried out at low voltage, the results so obtained are not accurate.

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