Ningbo Yinzhou Shengguang Motor Co.,Ltd.

This is the second important characteristic of a D.C. motor.It is linear and is used to calculate the no-load current and the currentwith the rotor stationary (start-up current)

The graph for this relationship does not vary with the supply voltage
of the motor. The end of the curve is extended in accordance with the torque and the start-up current    .
This torque constant is such that::C=Kc(I-Io)   The otational friction torque is Kc. Io.    The torque is therefore expressed as follows :C=Kc. I-Cf   Cf=Kc. Io
Kc = Torque constantr (N.m/A)           C = Torque (N.m)
Cd= Start-up Torque (N.m)                 Cf = Rotational friction torque (N.m)
I = Current (A)                Io = No-load current (A)               Id = Start-up current (A)
The gradient of this curve is called the "torque constant" of the