4. Regulation values of 5.6 per cent
indicate good speed regulation
100 per cent regulation is very poor
and means the motor stops altogether
when placed on load.
5. Example:
A DC shunt-connected motor runs at 1050
rpm (rev/per/min) on no load and slows to
990 rpm on full load. Find the speed
regulation.
12. Where
T = Torque in Newton-metres (Nm)
p = Number of poles
Φ = Flux per pole in weber
I = Total armature current
Z = Number of armature conductors
a = Number of parallel paths in the armature
(two parallel paths for wave and equal to the
number of poles for a lap winding).
13. Example:
A four pole dc motor has a lap-wound
armature of 30 coils, each with 20
conductors. If the flux per pole is 0.02 Wb
and the armature current is 19 A calculate
the torque produced.
