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What would cause a meter to read negative voltage across a DC motor?
Wiki User
∙ 8y ago
A DC motor generates power when it is rotating even when no supply is connected.
Wiki User
∙ 8y ago
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What instrument measures current and voltage?
Voltmeter.Current and voltage are two different things. They are closely related but a current does not imply a voltage and nor does a voltage imply a current.A volt meter is used to measure a voltage. The voltage may be across a battery or other power source. It may be across a component such as a resistor or a group of components. If a current is flowing through a resistor, there will be a voltage across the resistor. Similarly, if there is a voltage across a resistor, there will be a current flowing.Current is measured using an ammeter - Current is measured in amps, hence the name of the meter.The two meters together can be used to analyze most electronic circuits and they are the two most important items of test equipment in electronics. Devices called multi-meters are combined ammeters and voltmeters and are in every electronics engineer's toolbox.
What reading would you get if a voltmeter is placed in series across a load in closed circuit?
In series and across the load are contradictory statements. Some voltmeters are really capable of voltage, current and resistance measurements. To measure current the meter either has to be a clamp on type or one that goes in series with the load. You measure voltage drop across the load as described above.
How do you measure polarity?
In a DC circuit, just connect your meter across the source or electrical bus. The meter, because it is one of the newer digital ones, will work regardless of which way the leads are connected. If the leads are plugged into the meter correctly, the investigator need only look at the sign associated with the reading on the meter and the position of the leads. If the reading on the meter is "13.6 V" on a DC setting, then the red lead is connected to the positive side or negative rail, and the black to the negative side or negative rail. Conversely, if the reading is "-13.6 V" on a DC setting, the red lead is on the negative side or negative rail, and the black lead is on the positive side or positive rail. The DMM is a wonderful innovation and will allow someone making measurements to not have to worry about which way to connect the leads - as long as that someone pays attention to the sign displayed with the voltage reading.
How do you convert a 50 micro-amp DC meter to a 100 milli-amp meter?
with a resistor 300K in series with the 50 micro amperes DC meter
Maximum voltage a meter can handle?
A hand held test meter is usually rated for 1000 volts.
What causes a meter to read negative voltage across a DC motor?
The main cause for a meter to read negative voltage across a DC motor is a loose ground wire. The ground wire can be loose or may need to be cleaned.
Would cause a meter to read negative voltage across a dc motor?
A DC motor generates power when it is rotating even when no supply is connected.
Why is it possible to measure an electric potential across the terminals of a dry cell?
Batteries are a voltage storage device that hold a voltage potential until used. By using a volt meter you can find the stored voltage by placing the leads of the meter across the battery's positive and negative terminals.
When the voltmeter is connected across the open in the circuit the meter will indicate a voltage equal to the?
The source voltage.
Why would you get a negative voltage reading?
Because the meter is connected backwards
What determine the polarity of the voltage across a resistor?
A: Current flow only one way form positive to a less positive point. However it is possible to measure negative and positive voltage drop it the meter leads are reversed.
When is it important to make sure to match the polarity of the meter leads to the polarity of the circuit being tested?
This is important when meter cannot display negative values, e.g. it is analogous meter with scale. Most digital meters can display negative values. P.S. I am amateur in elecrtonics.
How do you measure alternating current voltage and resistance?
You measure current by inserting an amp meter in series with the circuit or using a clamp-on meter to measure current by induction. You measure voltage with a volt meter across the supply. You measure resistance in ohms across the resistance. Luckily all these functions are in the same meter in most cases.
How do you test 220 volts using a volt meter?
Make sure that the test meter is on the correct voltage scale. Place one lead on one of the conductors to be tested and the other lead on the other voltage source conductor. The reading you obtain will be the voltage potential between the two conductors.
How would you measure voltage passing through a light bulb using a digital multimeter?
Simply set the multi meter on DC voltage, which is denoted by a line with dotted lines under it. Then place the red lead on the positive side of the bulb and the black lead on the negative side. If you do this incorrectly it will be a negative number but the same number if the leads are reversed. If you have a bad bulb the meter will show all zero´s. Otherwise you´ll get something like 0.01 which is a good indicator for a working bulb. The voltage across the light bulb will be the same voltage as the supply. Regardless of whether the bulb is good or bad the voltage potential will still be there. You are measuring voltage not amperage.
4 capacitors 2.2uF 3.3uF 4.7uF and 5.6uF are connected in series with a power supply of 200 volts dc what is the voltage across each capacitor what is the formula?
Putting capacitors in series and then applying a DC voltage to them is not entirely useful. The voltage will cause a small current to flow into the capacitors, charging them to a total cumulative voltage of 200V. No further current will flow. If a meter is applied to one of the capacitors it's charge will cause a voltage measurement but it will quickly drop as the current flowing into the meter discharges the capacitor.
How do you find voltage across capacitors in a serial parallel circuit?
Voltage across all parallel capacitor's is same i.e. it is equal to supply voltage, it can be measured using digital volt meter (any high input impedance volt meter). When capacitors are in series; voltage drop depends on charge stored in the capacitor. it can be given by the formula V x V = 2 / (joules x capacitance). This voltage can also be measured using digital volt meter.
