4 point starter
A 4 Point Starter is almost similar in functional characteristics to 3 Point Starter . In the absence of back EMF, the 4 Point Starter acts as a current limiting device while the starting of the DC motor. 4 Point Starter also acts as a protecting device The basic difference in 4 Point Starter as compared to 3 Point Starter is that in this a holding coil is removed from the shunt field circuit. This coil after removing is connected across the line in series with a current limiting resistance R. The studs are the contact points of the resistance represented by 1, 2, 3, 4, 5 in the figure below. The schematic connection diagram of a 4 Point Starter is shown above The above arrangement forms three parallel circuits. They are as follows:- Armature, starting the resistance and the shunt field winding. Variable resistance and the shunt field winding. Holding coil and the current limiting resistance. With the above three arrangem...