Exam 18: Single-Phase Transformers

The amount of core material needed for a particular transformer is determined by the ____ rating of the transformer.

When testing a transformer, if one lead of an ohmmeter is connected to a primary winding lead and the other is connected to a secondary winding lead, you are checking the transformer for ____.

____________________ are often connected in series with a low-impedance load to prevent inrush current from becoming excessive.

If a transformer is connected additive, the polarity arrows point in the ____________________ direction.

A(n) ____________________ transformer is used to reduce the line voltage to the value needed to operate control circuits.

When a transformer has two primary windings, they are connected in ____________________ to operate at the lower voltage.

When a transformer has two primary windings, they are connected in ____________________ to operate at the highest voltage.

The ____________________ winding of a transformer is the power input winding.

If a transformer has a primary voltage of 480 volts and a secondary voltage of 240 volts, the turns ratio of this transformer is ____________________.

When testing a transformer, if one ohmmeter lead is connected to a transformer winding and the other is connected to the transformer frame, you are testing the transformer for ____.

The ____________________ winding of a transformer is the load winding.

The tape wound, or toroid, core transformer is constructed by tightly winding one long continuous silicon steel tape into a ____________________.

The ability of one coil to induce a voltage into another coil is called ____ induction.

In a distribution transformer, the center tap is grounded and becomes the ____ conductor.

The abbreviation for kilo-volt-amps is ____________________.

When testing a transformer for polarity, if the reading on the voltmeter indicates a voltage equal to the difference between the primary and secondary winding voltages, the windings are connected ____________________.

A(n) ____________________ is a magnetically operated machine that can change values of voltage, current, and impedance without a change of frequency.

When the primary of a transformer is connected to power but there is no load connected to the secondary, the transformer is essentially a(n) ____________________.

An isolation transformer whose main purpose is to reduce voltage spikes will have a turns ratio of ____.

An isolation transformer that has more than one set of lead wires connected to the primary or secondary windings is called a ____________________-tapped transformer.