Unit 2-2 Lesson 2
Current is measured in ? . a. amperes b. ohms c. volts d. watts
A
Most digital multimeter displays include a(n) ? to show changes and trends in a circuit. a. analog scale b. bar graph c. diode test mode d. MIN MAX mode
B
One problem with small 3-phase voltage imbalances is that they cause high ? imbalances. a. core b. current c. power d. resistance
B
The ? value of a sine wave is the maximum instantaneous value of either the positive or negative values in the sine wave. a. average b. peak c. positive d. rms
B
When a 3-phase current unbalance exceeds ? , a test for voltage unbalance should be performed. a. 3% b. 10% c. 20% d. 30%
B
? leakage current is current that flows from areas on conductors where insulation has been removed to allow electrical connections. a. Capacitive b. Conductive c. Surface d. Terminal
C
A(n) ? is a test meter that measures resistance, the opposition to the flow of electrons in a circuit. a. ammeter b. chronometer c. ohmmeter d. voltmeter
C
AC voltage is voltage in a circuit that reverses its direction of flow at regular intervals, and is stated and measured as peak, average, or ? value. a. MIN/MAX b. regular c. rms d. standard
C
An ohmmeter is used to measure the ? . a. amperage b. direction of voltage flow c. resistance d. voltage
C
In-line ammeters require the circuit to be ? so the ammeter can be inserted into the circuit to acquire a reading. a. closed b. low voltage c. opened d. parallel
C
Many test instruments include a ? in the current-measuring circuit to prevent damage caused by excessive current. a. bypass b. circuit breaker c. fuse d. relay
C
A clamp-on ammeter is a test instrument that measures current in a circuit by measuring the strength of the ? around a single conductor. a. ampacity b. electromotive force c. inductive reactance d. magnetic field
D
One advantage of voltage testers is that they have a lower impedance (resistance) and draw more current than voltage indicators, which allows them to be used for testing ? . a. insulation b. job order motors c. job order wiring d. GFCIs
D
Voltage measurements using the ? on a digital multimeter are useful in identifying low voltage conditions. a. analog scale b. bar graph c. diode test mode d. MIN/MAX mode
D
AC current is current in a circuit that flows in one direction only. Select one: True False
False
Most analog multimeters do not have calibrated scales that correspond to the different selector switch settings. Select one: True False
False
Voltage indicators only indicate that voltage and current are present; they do not indicate the actual voltage. Select one: True False
False
A clamp-on ammeter is typically used to measure current in a circuit with over one ampere of current. Select one: True False
True
A megohmmeter is a high-resistance ohmmeter used to measure insulation deterioration on various wires by measuring high-resistance values during high voltage test conditions. Select one: True False
True
A permanent test instrument is a device that is installed in a process, or at a bench, to continually measure and display quantities. Select one: True False
True
A portable test instrument is used to take real-time (momentary) measurements. Select one: True False
True
A voltage indicator needs only to be near a voltage source to indicate the presence of voltage. Select one: True False
True
Measuring current is useful because only current can be used to determine how much a circuit is loaded (working). Select one: True False
True
When using an ohmmeter, the resistance of all components connected in parallel with the component being tested affects, and typically lowers, the resistance reading. Select one: True False
True
When voltage measurements are different from what is expected, the voltage measurement is most likely to be lower than normal. Select one: True False
True
