Self-Test A-4.3 Electrical Testing Instruments

Complete Self-Test A-4.3 and check your answers.

1. 1. Match the digital multimeter symbol to its correct description.
      

      AC Voltage	___________	a.
      DC voltage	___________	b.
      Resistance	___________	c.
      AC or DC voltage	___________	d.
      Low Battery	___________	e.
      Continuity beeper	___________	f.
      Overload	___________	g.
      Microamperes	___________	h.

       

   2. The most common clamp-on ammeters are available for AC currents only.
      1. True
      2. False

       

   3. When using an in-line ammeter to measure current in a circuit, what must you ensure when connecting the multimeter?
      1. The power is off in the circuit
      2. The multimeter is connected near the source
      3. The multimeter is connected in series with the circuit
      4. The multimeter is connected in parallel with the source or load

       

   4. When testing for ohms, the power must be left on in the circuit.
      1. True
      2. False

       

   5. When testing a circuit for voltage, how must the meter be connected?
      1. In parallel with the circuit
      2. In series with the circuit
      3. To a de-energized circuit
      4. With both leads grounded

       

   6. When testing for continuity in a circuit, what must be ensured?
      1. That the circuit is powered
      2. That the meter is grounded
      3. That the source has a short circuit
      4. That the circuit is de-energized

       

   7. Test leads must have a category rating that is equal to or less then the rating of the tester.
      1. True
      2. False

       

   8. An AC voltage waveform changes polarity constantly with time, so it is not necessary to ensure correct polarity when connecting the test leads.
      1. True
      2. False

       

   9. When using a clamp ammeter on a two-wire circuit, the two electromagnetic fields will cancel each other out if the meter is clamped around both wires at once.
      1. True
      2. False

       

   10. The ohmmeter is designed so that it will display 0 ohms when the test leads are left open. (zero external resistance)
       1. True
       2. False

   Answer Key: Self-Test A-4.3 is on the next page.