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They read low resistance values very well. I measured several dead shorts today accurately with a digital voltmeter.
However, when attempting to measure LARGE amount of resistance, the current generator in a standard digital voltmeter may fail to effectively penetrate the medium being measured. It is for this reason that Meggers (Mega-Ohmmeters) are used to measure high amounts of resistance. They usually employ a hand crank to develop the current needed to effectively flow through the medium being measured.
Sometimes digital voltmeters can be very inaccurate if they are measuring something that matches the impedance of the meter (loading effects of the voltmeter), but that is another story.
What else can I help you with?
What is critical resistance of the field circuit of a DC generator?
The value of resistance of shunt field winding beyond which the shunt generator fails to build up its voltage is known as " critical resistance at a given speed it is the maximum field resistance with which the shunt generator excite.
If temperature increases than the resistance increase or decreases?
If temperature increases the resistance will also increase. This is why a light bulb is a non ohmic conductor. As the light bulb filament gets hotter its resistance will increase.Additional CommentsIt depends upon the material involved. In general, for pure metal conductors an increase in temperature will cause their resistance to increase. For insulators, an increase in temperature will cause their resistance to decrease -which is why excessive temperature is often the main reason why insulation fails. Alloys can be manufactured that will maintain a relatively constant resistance over a wide range of temperatures.Temperature affects resistance indirectly. What is actually being affected is the material's resistivity. Resistivity is one of the factors that determines resistance.The resistance of any given material can be calculated over wide range of temperatures, using the temperature coefficient of resistance for that material.
How to do the megger test in electric motor?
Briefly, a megger test is testing an electric circuit at load. The circuit might prove good at normal resistance measuring but fails when applying high voltage. Read the megger result correctly, every electric circuit will fail if stressed high enough. Disconnect any servo drive or frequency controller before testing.
Do diodes obey Ohms law?
Diodes do not obey Ohm's Law, at least when viewed as an individual component. When doing circuit analysis, however, you can make the case that, for a specific situation, they do. In fact, using this technique, everything "obeys" Ohm's law. In the simple case of a resistor, operated within its limits, Ohm's Law works just fine. Voltage is current times resistance. As voltage goes up, current goes up proportionately. You can predict the voltage or current knowing the other along with resistance. A diode, on the other hand, is non linear. As you apply voltage across it in the forward direction, it initially has high resistance. All of a sudden it has low resistance as it begins to conduct. As you increase the current, the resistance decreases, so the voltage drop is relatively (though not exactly) constant. At a certain point, around when you exceed the maximum forward current, the diode fails. In the reverse direction, an ordinary diode seems to have high resistance, until you reach about max reverse voltage, at which point the diode fails. In the case of a zener diode, reverse behavior is similar to forward behavior, except at a different voltage. Even though the diode does not obey Ohm's law, you can still use Ohm's Law to analyze the circuit. You just have to remember that the dynamic resistance of the diode changes as a function of the applied voltage. The value of Ohm's Law becomes evident when you consider that, at each static condition of the circuit, you do know the voltage and current through the diode and, as a result, you can use Ohm's law to calculate its dynamic resistance. This will allow you to extend the analysis by back substitution and simplification until you know more and more about the circuit.
If one bulb fails and all the others turn off you are dealing with a?
A circuit of a series configuration.
If the resistance temperature detector fails. What increases?
resistance
How can you reset the digital odometer?
If you're talking about the basic cyclocomputer there's usually a button on the underside that'll reset it. If that fails you can always pop the battery out - assuming you know how to enter the values for wheel size and that afterwards,
Is there a way to test the crankshaft sensor on a 97 Ford Taurus?
You can either use a multimeter or a lab scope. When using a multimeter check the 12 volts from the battery at the connector then take the sensor out and check the resistance from the sensor's pins. Check the specs from the manufacturer. Although a correct spec does not necessarily means the sensor is good. This sensor normally fails when they are hot and not when they are cold. The advantage of using a lab scope is that you can test the sensor while the car is hot and running and by seeing the wave
What are the disadvantages of integrated service digital network?
An external power supply is required. The telco's don't supply power for ISDN lines. If the power fails, the phones won't work.Special digital phones are required or a Terminal Adapter to talk to the existing POTS devices.It is very expensive to upgrade a central office switch ($500,000+) to ISDNIf the ISDN fails - the phone fails.
What is critical resistance of the field circuit of a DC generator?
The value of resistance of shunt field winding beyond which the shunt generator fails to build up its voltage is known as " critical resistance at a given speed it is the maximum field resistance with which the shunt generator excite.
How you calculate the resistance of a capacitor?
There's nothing to calculate. Until it fails and must be replaced, the resistance ofa capacitor is infinite. A measurement with a typical ohmmeter will show that thecapacitor is open.
How do you put pictures on a digital photo album?
Usually there is an instruction booklet that will take you step by step in the process of how to put pictures on your new digital album. If all else fails, try reading the instructions first.
How do you test ignition control module Datsun 280zx?
To test the ignition control module (ICM) on a Datsun 280ZX, first, ensure the vehicle is turned off and disconnected from the battery. Use a multimeter to check the resistance of the ICM's terminals according to the specifications in the service manual. Additionally, you can perform a functional test by checking for proper voltage output while cranking the engine. If the module fails these tests, it may need to be replaced.
Where can one purchase digital night vision devices?
You can purchase digital night vision goggles in hunting stores and sometimes in gun shops. If all else fails you can shop online for them, Amazon and eBay should be your first start.
How do series circuits and parallel circuits compare?
In series circuits, the current flows through each component sequentially, so if one component fails, the entire circuit will fail. In parallel circuits, each component has its own separate branch, so if one component fails, the others will continue to operate. Additionally, the total resistance in a series circuit is the sum of individual resistances, while in a parallel circuit, the total resistance is less than the smallest individual resistance.
What is digital asset management and how will it benefit you?
Digital Asset Management is the practice of backing up your computer files, or example onto an external hard drive. It can come in very handy when your hard drive fails, because you will have a backup of your files, and none will be lost.
What happens to the resistance of silicon as its temperature increases?
A: As temperature increases its resistance increases. Like all silicon diodes it will reach a point where the temperature coefficient is zero but it is at such elevated temperature to make it invaluable
