Exam 8: Measuring Instruments

The ____________________ is the ratio of the number of turns of wire in the transformer primary winding to the number of turns of wire in the transformer secondary winding.

The input impedance used to limit the flow of current through digital meters is accomplished by using ____.

The ____ must provide its own source of power.

When the selector switch of a meter is turned to a new scale, steps of ____ are inserted in the circuit to increase the range or are removed from the circuit to decrease the range.

Most AC ammeters use a ______________________________ to change scale values instead of shunts, which can be used to increase range but cannot be used to decrease range.

A(n) ____________________ is used to measure power in an electrical circuit.

If a DC voltmeter is connected to an AC circuit with an applied voltage of 240 V, the meter will read ____ volts.

____________________ ohmmeters measure resistance by measuring the amount of voltage-drop across an unknown resistance.

If a clamp-on ammeter is clamped around more than one power line of a 240 V circuit, the meter will read ____ volts.

Digital meters that do not contain a range setting control are known as ____ meters.

The test instrument used to measure the resistance of an electrical circuit is called a(n) ____________________.

When a toroid current transformer is used to measure AC current, the main power line acts as the ____ and is considered to be one turn.

A voltmeter is designed to be connected in ____ with the circuit to be measured.

A(n) ____ is a low-resistance device used to conduct most of the circuit current away from the meter movement.

When a large amount of AC current must be measured, current transformers known as ____________________, that have a standard secondary current rating of 5 A -- AC, are used.

A _________________________ is a device used to measure voltage, but does not contain a meter movement or a digital display.

When reading a digital meter, the symbol "mV" indicates ____________________.

An ammeter is used to measure current and must be connected in ____ with the load.

A(n) ____ must never be connected to a circuit when the power is turned on.

Any number can be multiplied by ____________________ by moving the decimal point one place to the right, and any number can be divided by ____________________ by moving the decimal point one place to the left.