Electrical Engineering

# Write the universal torque equation and derive the characteristic of impedance reactance and mho relays?

###### Wiki User

###### March 03, 2013 5:13AM

## soumitro paul; student of a.p.c roy polytechnic 2013

answer

## The universal relay torque equation is

T=k1I2+k2V2+k3VIcos(a-e)+K

where

T= maximum torque

V= R.m.S magnitude of voltage

I= R.M.S magnitude of current

The spring torque will be K .

a= angle between V&I

e=max torque angle

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