Key Specifications of DC Machines: Guide and Overview

Output Power:      KW (for generaators),

KW or HP (for motors)

Voltage:           V volt.

Speed:             N rpm.

Rating:            Continuous or Short time.

Temperature rise:  0⁰C for an ambient temperature of 40⁰C.

Cooling:           Natural or forced cooling.

Type:              Generator or motor, separately excited or

self-excited-shunt, series,or compound.

 

• Working principle and construction of DC Generator

If compound then,

Type of connection –    long or short shunt,

Type of compounding –   cumulative or differential,

Degree of compounding – over, under or level.

With or without inter poles, with or without compensating

windings, with or without  equalizer rings in case of lap

winding.

Voltage regulation: Range and method (in case of generators).

Speed control:     Range and method of control (in case of motors)

Efficiency:        Should be as for as possible high (As the

efficiency increases, cost of the machine also increases).

Type of enclosure: Based on the field of application –

totally enclosed, screen protected, drip proof, flame proof,

etc.,

And finally Size of the machine etc.,