Answer / raghavendran r

A decrease in Excitation Causes
1) Decrease in Terminal Voltage.
2) Increase in Stator Current.
3) Decrease in Power factor.

If further reduced, it might cause Pole slipping and Gen
coming out of synchronism.

Answer / janardhangc

in the case of synchronus generator by varying the
excitationthe teminal voltage can be varied.but in the case
of the motor the speed can be varied because as we know
that speed is invesly propotional to flux or field strength.

how can you calculate the value of external resistance inserted in a slipring industion motor? (eg. 110 kw / 990 rpm/50Hz/stator v-415/stator Amp-195/Rotor V-440/Rotor amps- 151.)

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Define end float in a motor?

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