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A: A multimeter is an instrument design to measure ohms volts and amps. So to measure amps a shunt is provided to allow a sample of the current to be measured as a function of voltage.
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Why is it harder to measure amperage than voltage whit a digital multimeter?
Because to measure amperage you must connect the multimeter in series , in order to do so the circuit must be broken first. In the case with voltage measurements the multimeter probes must be connected in parallel which is far easier because connecting the multimeter this way the circuit will remain intact.
Why is multimeter not used for insulation testing instead of a megger?
No, you cannot use a multimeter in place of a megger. The megger is used to measure insulation resistance, which could be hundreds of megohms or so. In order to do that, you need a high voltage so as to develop the current needed to sense the resistance. Using an ordinary multimeter would not work as the applied voltage is not high enough, causing the sensed current to be too small to detect.
Why is the rotor winding of a synchronous motor connected to an external resistance during start up?
because at start the motor draws larger quantity of current and this may affected the rotor windings in order to limit current always resistance is connected.
How do you find transistors?
A transistor have 3 legs. B, C and E. You can measure the resistance between the legs with a multimeter in order to get a good indication of its condition. If the resistance between any of the 3 legs are close to 0 Ohm (often 0.1 to 6 Ohm) then the transistor is most likely burned and no good any more. If the resistance is above 200 Ohm, then the transistor is most likely burned as well. Note: A good transistor will measure different values depending on where you put probes. If the probes indicate an awful lot of resistance then try to switch the probes and measure again. If resistance is the same, then it is burned. If not, then it is likely OK. It is often difficult to tell if your transistor is actually a Fet or a Darlington. try to search internet for proper data on your 'transistor'. Small signal transistors are often burned open between legs (very large resistance) where as large transistors often shortcut between legs (Very low resistance between legs). I find the C and E leg to be easiest to diagnose a transistor on. If the resistance both ways are the same, then it is no good. Note: In order to 100% determine a transistors condition, then you often would need to desolder it first. All the other components on a printboard will make it harder to diagnose (unless it has shortcut). ANSWER: pay attention to the probes polarity and whether is an PNP or NPN . For an NPN The positive lead goes to the base and either other lead will show resistance reverse the leads and repeat now both reading should be hi resistance. For the PNP SAME PROCEDURE EXCEPT THE POLARITY OF THE LEADS ARE REVERSED
What is the total resistance in the series circuit where E equals 240 R1 equals 100 R2 equals 500 R3 equals 600?
1). You don't need the voltage 'E' in order to calculate the total resistance. The totalresistance is the same whether the circuit is connected to a big battery, to a smallbattery, to a bicycle pump, or lying in the back of the desk drawer.2). In a series circuit, the total resistance is just the sum of the individual resistances.In this example, the total resistance isR1 + R2 + R3 = 100 + 500 + 600 = 1,200 ohms .
Why is it harder to measure amperage than voltage whit a digital multimeter?
Because to measure amperage you must connect the multimeter in series , in order to do so the circuit must be broken first. In the case with voltage measurements the multimeter probes must be connected in parallel which is far easier because connecting the multimeter this way the circuit will remain intact.
Why is multimeter not used for insulation testing instead of a megger?
No, you cannot use a multimeter in place of a megger. The megger is used to measure insulation resistance, which could be hundreds of megohms or so. In order to do that, you need a high voltage so as to develop the current needed to sense the resistance. Using an ordinary multimeter would not work as the applied voltage is not high enough, causing the sensed current to be too small to detect.
Why one of the leads of resistor connected in electronic circuit is opened while measuring its resistance?
You open one of the leads of resistor connected in electronic circuit while measuring its resistance in order to not introduce error cause by other components in the circuit.
How can you convert galvanometer into ammeter?
Since Galvanometer is a very sensitive instrument therefore it can't measure heavy currents. In order to convert a Galvanometer into an Ammeter, a very low resistance known as "shunt" resistance is connected in parallel to Galvanometer. Value of shunt is so adjusted that most of the current passes through the shunt. In this way a Galvanometer is converted into Ammeter and can measure heavy currents without fully deflected.
Why the rotor winding of a synchronous motor is usually connected to an external resistance during start up?
because at start the motor draws larger quantity of current and this may affected the rotor windings in order to limit current always resistance is connected.
Why must voltmeter be connected in parallel with the circuit component?
Because, by definition, a voltage is the difference in potential between two different points. So the voltmeter must be connected across those points in order to measure that voltage -i.e. in parallel with the points.B
What defines a shape?
Every component: the length of each line, the measure of each angle, the order in which the lines are connected, the order of the angles, whether these orders are clockwise or anti-clockwise.
What is the resistance you n the circuit when 10v2k greek symbol along with4k greek symbol?
In order to calculate the effective combined resistance, we need to know whether they are connected in series or in parallel. We don't know which circuit configuration is indicated when you say "along with".
How much voltage is used to measure resistance?
The voltage needed to make a resistance measurement varies in proportion to the Ohms value being measured. Resistance measurements in the order of thousands and up to one Megohm are low enough to be made with a 1.5 volt or similar cell. However, resistance measurements in the order of hundreds to thousands of Megohm will require a higher voltage of up to 500 Volts DC. A Megger is a device that uses hundreds of volts to make resistance measurements.
Why does an ammeter have a low resistance while a voltmeter has high resistance?
I am going to assume that you mean low "resistance" in an open circuit test and are performing this with a multimeter. An ammeter works by place a very small amount of resistance in series with a circuit and then measuring the Voltage drop across the resistance. The Voltage is directly proportional to the current as given in ohms law: E = I x R If you are measuring the resistance through the ammeter it will have a very low resistance and impedance.
Why is the rotor winding of a synchronous motor connected to an external resistance during start up?
because at start the motor draws larger quantity of current and this may affected the rotor windings in order to limit current always resistance is connected.
Does a volt meter takes power from the system?
No it does not. A volt meter only reads the current that is passing through it.AnswerAll instruments draw some (albeit tiny) current from the circuit under test in order to operate. So, if this is what you mean by 'taking power from circuit', then the answer is yes, it does.Instruments also change the normal resistance of the circuit being tested -for example, ammeters increase the resistance of the circuit into which they are connected, while voltmeters decrease the circuit resistance across which they are connected. So adding a voltmeter (or an ammeter) to a circuit affects the operation of that circuit to some degree. To minimise this interference, it is important that an ammeter's internal resistance is very much lower than the circuit's resistance, and a voltmeter's resistance is very much higher than the circuit's resistance.
