IDA-201 Midterm Exam Prep pt.2

A(n) _____________ is used commonly in open split-phase motors to disconnect the start winding from the electrical circuit when the motor reaches approximately 75% of its rated speed.

• centrifugal switch

• end bell

• squirrel cage rotor

• winding thermostat

Power supply, work requirements, motor insulation class, bearing types, and mounting characteristics are all factors that can influence

• belt selection.

• motor selection.

• motor rotation.

• pulley diameter.

The two types of lubrication systems for sleeve bearings are ___________.

• oil port and drip

• splash and permanently lubricated

• oil port and permanently lubricated

• drip and splash

The voltage range for an electric motor is usually within + or - _________%.

• 5

• 1

• 10

• 20

When an open motor gets up to speed, the ___________ switch takes the start winding out of the circuit.

• inverter

• transistor

• centrifugal

• rectifier

The rotating portion of a motor that is made of iron or copper bars bound on both ends with aluminum is called the

• end bell.

• rotor.

• winding

• stator.

On most _____________ motors, the rotation can be reversed by disassembling the motor and turning the stator over.

• shaded-pole

• three-phase

• capacitor-start

• permanent split-capacitor (PSC)

The inverter

• varies the frequency.

• contains a capacitor bank.

• adjusts the DC voltage.

• smooths out the AC power.

An instrument often used to check the alignment of two shafts is the

• sling psychrometer.

• micrometer.

• manometer.

• dial indicator.

The motors most often used in a residential application are ___________ motors.

• single-phase

• 460 V

• three-phase

• 277 V