A 6-pole dc generator is running at 1200 rpm. What is the frequency of current in the armature winding?

An 6-pole d.c generator has 300 armature conductors, and a useful flux of 14 mWb per pole. What will be the em.f. generated if it is lap-connected and runs at 1420 rpm? What must be the speed at which it is to be driven produce the same e.m.f. if it is wave-wound?

A 4 pole , lap wound dc shunt generator has a useful flux per pole of 0.07 Wb. The armature winding consists of 220 turns each of 0.004ohms resistance. Calculate the terminal voltage when running at 900 rpm if the armature current is 50 A

Armature reaction in an alternator primarily affects:   A: rotor speed  B: terminal voltage per phase  C: frequency of armature current  D: generated voltage per phase

Calculate the flux per pole required on full-load for a 50 kW, 400 V, 8-pole, 600 r.p.m. d.c. shunt generator with 256 conductors arranged in a lap-connected winding. The armature winding resistances is 0.1 Q, the shunt field resistance is 200 Q and there is a brush contact voltage drop of 1 V at each brush on full- [0.162 Wb] 5. load. Calculate the flux in a 4-pole dynamo with 722 armature conductors generating 500 V when running at 1000 r.p.m. when the armature is (a) lap connected (b) wave connected. [(a) 41.56 mWb (b) 20.78 mWb] (City & Guilds, London) 7. A 4-pole machine running at 1500 r.p.m. has an armature with 90 slots and 6 conductors per slot. The flux per pole is 10 mWb. Determine the terminal e.m.f. as d.c. Generator if the coils are lap-connected. If the current per conductor is 100 A, determine the electrical power. [810 V, 324 kW] (London Univ.) 8. An 8-pole lap-wound d.c. generator has 120 slots having 4 conductors per slot. If each conductor can carry 250 A and if…

Examine the saddle torque of induction motors and the effect of different groove structures on the saddle torque.

a dc shunt generator has a generated emf 240v and a constant value of 8, if it is running at 1500 rpm, what is flux (in mwb) is being developed inside the machine?

1A. Which of the following is/are a method of providing field excitation for a DC generator. a) separately excited shunt b) self-excited series c) self-excited shunt d) all of the above 1B. Which type of field winding typically has the higher resistance? a) series b) shunt

a. Explain how a rotating magnetic field is produced in a three-phase induction motor. b. Explain the rotor action on a three-phase squirrel cage motor when the load increases from NO-LOAD to rated FULL- LOAD