Description : When troubleshooting electronic equipment, you should use a high impedance multimeter ________________. A. to prevent excess current flow through the meter that would damage it B. for AC measurements only ... being tested D. so as not to load down the circuit and obtain erroneous voltage readings
Last Answer : Answer: D
Description : When taking a voltage measurement, which lead of the voltmeter should you connect to the circuit first?
Last Answer : Ground.
Description : You are calibrating a multimeter using internal batteries to supply power for resistance measurements. However, you are unable to adjust the pointer to 'zero' using the adjustment knob. Therefore, you should ... change scales to the R X 100 scale and adjust using the 'zero ohms' adjusting knob
Last Answer : Answer: A
Description : Why should you always use the highest range when connecting a voltmeter to a circuit?
Last Answer : To prevent excess current through the meter movement.
Description : When checking a diode with an ohmmeter, what is indicated by two high resistance measurements?
Last Answer : The diode is open or has a high-forward resistance.
Description : To test fuses in an energized circuit, you should use a ____________. A. low voltage light bulb B. megohmmeter C. voltmeter D. resistance meter
Last Answer : Answer: C
Description : A low voltage source is being used for testing armature coils. A coil short circuit will be indicated by a _______. A. high voltage reading, while the other coil readings will have an ... the other coil readings are steady D. steady voltmeter reading, while the other coil readings are fluctuating
Last Answer : Answer: B
Description : What is the polarity of voltage at point 'Z' in the circuit shown in the illustration? EL-0085 A. It will always be positive. B. It will always be negative. C. It depends on the instantaneous polarity at point 'W'. D. It cannot be determined without a voltmeter.
Description : To limit the current flow through a DC voltmeter to as low a value as possible, the moving coil circuit is provided with a/an _____________. A. high series resistance B. high parallel resistance C. series inductor D. external shunt
Description : How does the supply voltage affect the accuracy of Wheatstone bridge measurements?
Last Answer : As the supply voltage increases, bridge components may heat up and become less accurate.
Description : The frequency response of test equipment refers to what aspect of ac voltage measurements?
Last Answer : the range of frequencies that can accurately be measured.
Description : On what range should you set the voltmeter prior to taking a voltage measurement?
Last Answer : Highest.
Description : If an ac voltmeter is connected between the S2 and S3 windings on a TX, at what two rotor positions should the voltmeter read maximum voltage?
Last Answer : . 150º and 330º
Description : A resistance in a circuit of unknown value is to be tested using the voltmeter/ammeter method. Therefore, the meters should be connected with _____________. A. both meters in series with the ... parallel with the resistance D. the ammeter in parallel and the voltmeter in series with the resistance
Description : How is a voltmeter connected to the circuit to be measured?
Last Answer : In parallel.
Description : A device which can be used to check the calibration of a circuit breaker is a _________________. A. 500 volt megohmmeter B. portable low voltage high current testing unit C. standard digital multimeter D. clamp-on voltmeter
Description : Voltage measurement in a high impedance circuit requires a voltmeter with
Last Answer : high input impedance
Description : When using a multimeter for resistance measurements, it should be calibrated by clipping the loose ends of the leads together and _____________. A. setting the instrument pointer at 'zero' ohms B. ... the plus and minus terminals D. using a special purpose resistance measuring instrument (a bridge)
Description : Full scale Ammeter reading is 10 mA, Voltage across Ammeter is 100 mV. Then for 100 A measurements the power loss in the circuit is a) 1 W b) 10 W c) 100 W d) 1000 W
Last Answer : Ans: 10 W*
Description : A series circuit consisting of three resistors has a current of 3 amps. If R1 = 20 ohms, R2= 60 ohms, and R 3 = 80 ohms, what is the (a) total resistance and (b) source voltage of the circuit?
Last Answer : (a) 160 ohms. (b) 480 ohms
Description : A circuit is to be designed in which a capacitor must charge to 40 percent of the maximum charging voltage in 200 microseconds. The resistor to be used has a resistance of 40,000 ohms. What size capacitor must be used?
Last Answer : 0.1 microfarads 40% from the graph = 0.5
Description : When used for taking resistance measurements, a volt-ohm-milliammeter is normally powered by _____________. A. a hand cranked generator B. internal storage batteries C. the current in the circuit being tested D. a step down transformer
Description : A multimeter may be damaged by taking a _____________. A. voltage reading while in the ammeter mode B. current reading while in the voltmeter mode C. resistance reading while in the ammeter mode D. resistance reading while in the voltmeter mode
Description : If the approximate voltage to be measured in a circuit is not known, you should _____________. A. use the lowest voltage range on the voltmeter B. connect the meter in series with the circuit C. only have to calibrate the meter before using it D. use the highest voltage range on the voltmeter
Description : An open shunt field in a direct current machine may be located by connecting the field circuit to an external power source, equal to the rated field voltage or less, and tested with a voltmeter from ... C. any suitable ground to any available line lead D. any field pole to each field coil lead
Description : ___________ is device that measures the internal open circuit voltage of an equivalent noise generator having an impedance of 600Ω and delivering noise power to a 600 Ω load. A. Psophometer B. Barometer C. Reflectometer D. Voltmeter
Last Answer : A. Psophometer
Description : An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be (1) unaffected (2) decreased (3) increased (4) either decreased or increased depending on the direction of the DC field
Last Answer : An unshielded moving iron voltmeter is used to measure the voltage in an AC circuit. The stray DC magnetic field having a component along the axis will be either decreased or increased depending on the direction of the DC field
Description : The voltage of a circuit is measured by a voltmeter having input impedance comparable with the output impedance of the circuit thereby causing error in voltage measurement. This error may be called as_________.
Last Answer : error caused by misuse of instrument
Description : In the circuit diagram shown in Fig. 4.53, a voltmeter reads 30 V when connected across `400 Omega` resistance. Calculate what the same voltmeter read
Last Answer : In the circuit diagram shown in Fig. 4.53, a voltmeter reads 30 V when connected across `400 ... when it is connected across `300 Omega` resistance.
Description : In the given circuit, the voltmeter records 5 V. The resistance of the voltmeter in `Omega` is
Last Answer : In the given circuit, the voltmeter records 5 V. The resistance of the voltmeter in `Omega` is A. 200 B. 100 C. 10 D. 50
Description : By mistake, a voltmeter is connected in series and an ammeter is connected in parallel, with a resistance in an electrical circuit. What will happen t
Last Answer : By mistake, a voltmeter is connected in series and an ammeter is connected in parallel, with a ... be damaged D. Only the voltmeter will be damaged
Description : Which of the instruments listed should always be connected in series with a circuit? A. Ammeter B. Megohmmeter C. Wattmeter D. Voltmeter
Description : Radar surface-angular measurements are referenced to true north and measured in what plane?
Last Answer : Horizontal plane.
Description : What are the three units of measure most commonly used when referring to af power measurements?
Last Answer : DB, dBm, and vu.
Description : Kelvin bridges are well suited for what type of measurements?
Last Answer : Small values of resistances
Description : When you are measuring a component using a bridge, what is the most common cause of inaccurate measurements?
Last Answer : The capacitive and inductive characteristics of the test leads.
Description : Power measurements performed with calorimeters are based on what three variables?
Last Answer : Temperature, mass, and time.
Description : For power measurements, what advantage does an electronic wattmeter have over an electrodynamic wattmeter?
Last Answer : Electronic wattmeters are capable of measuring high-fequency signals.
Description : When is an optical power meter measurement recommended for conducting field measurements on installed optical fiber cables or cable plants?
Last Answer : When an installed optical fiber cable or cable plant is less than 50 meters in length.
Description : Why is a dead-zone fiber placed between the test fiber and OTDR when conducting attenuation measurements?
Last Answer : To reduce the effect of the initial reflection at the OTDR
Description : Why do end users perform fiber geometry measurements in the laboratory?
Last Answer : To reduce system attenuation and coupling loss resulting from poor fiber fabrication.
Description : What two properties of the launch condition may affect multimode fiber attenuation measurements?
Last Answer : . Launch spot size and angular distribution.
Description : List the fiber geometrical measurements performed in the laboratory.
Last Answer : Cladding diameter, core diameter, numerical aperture, and mode field diameter.
Description : Prior to substituting a diode, what measurements should you take to determine its condition?
Last Answer : Voltages and resistances.
Description : What are the advantages of connecting ammeters in parallel when performing current measurements?
Last Answer : Decreased internal meter resistance, greater accuracy, and greater current range.
Last Answer : For measurements on high voltage capacitors, the suitable bridge is Schering bridge.
Description : Which of the electrical properties listed will always be the same for each component in a parallel circuit? A. Impedance B. Current C. Resistance D. Voltage
Description : A temperature instrumentation system for an engine room console consists of a resistance temperature detector (RTD), a measuring bridge circuit, and a meter (or alarm circuit).Which of the following ... is zero. D. The input voltage of the resistance bridge is the constant temperature signal.
Description : Why would you use a hook-on voltmeter instead of a multimeter?
Last Answer : To measure current safely and easily (with no need to disconnect the wiring of the circuit).
Description : What should a voltmeter read when a TX is set on coarse zero?
Last Answer : Approximately 37 volts.