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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.
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Why would you get a negative voltage reading?
Because the meter is connected backwards
How do you connect energy meter in circuit?
pressure coil or voltage coil across the supply and the current coil in series.
Can watt meter negative reading?
Yes. This is usually an indication that either its current coil or its voltage coil has been wired incorrectly.
When the ammeter reading is zero and there are four resistor connected in seriesusing voltmeter identify which resistor causes the problem?
The ammeter is reading zero because there is no current flowing. This is because one of the resistors is faulty; the faulty resistor has an "open circuit" (open circuit means there is a broken connection). We know that: Ohms law is: V = I x R (voltage = current x resistance) Therefore because there is zero current in each resistor there will be zero voltage across each resistor. However we also know that: Kirchhoff's voltage law is: V1 +V2 +V3 + … = Vs (the sum of the voltage drops accross each component in a circuit MUST equal the supply (or battery) voltage). But if all the resistors are zero volts, then what component equals the supply (or battery) voltage? The battery voltage is developed across the open circuit… therefore the resistor which is faulty will have a voltage across it equal to the battery voltage. That easy to measure with a volt meter! hope this helps
What happens if a silicon diode measures high value of resistance with the meter leads in both positions?
If the meter is developing more than the necessary forward breakdown voltage of the diode, typically 0.7 volts, then the diode is bad. However, some meters do not generate enough voltage in resistance mode to bias the diode on, unless you flip a switch that enables diode test mode. Use another meter at the same time to measure the voltage across the diode and compare that with the diode's published forward breakdown voltage.
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.
What 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.
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.
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.
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.
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.
What is the effect if the polarity of voltage to be measured is not properly observed?
An analogue meter will deflect the needle the wrong way. A digital meter will show a negative value.
How do you measure the voltage on a car alternator?
get a multi meter that reads dc voltage & touch the black (negative -) wire to the negative battery post & the red (positive +) wire to the positive battery post with car running. car off is battery voltage, car on is alternator voltage.
