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Why resistors have tolerances?
Some design engineers that make electronic circuits specify tolerances in the resistors because a resistor that is too out of spec would not operate properly. A resistor with a brown band I believe is within 20%, a black is 10%, and gold is 5%. So if a resistor is rated at 3000 ohms, depending upon the band, it can vary a certain percentage. Resistors with the gold band I believe are called "precision resistors". The more "precision" the resistor is, the more it costs. To keep costs low, tolerances are sometimes included to alert the assembler that a precision resistor may not be necessary. For instance if a value of 3000 ohms can be within 20% then a cheap resistor may be used and is not critical in the circuit. The tolerances are introduced in manufacturing of resistors because practically, we can achieve 100% correct resistance. So, a tolerance range is indicated to make aware the users to select the proper resistor according to their application.
In roughness measureing system what is RMS value?
RMS value is defined as "The amount of ac supply required to make same heat effect in resistor , which is made by dc current, in that resistor"
What opportunities that can help make south Africa a manufacturing trading nation?
it can make money from exports
Why you use resistor with variable resistor?
Often we want to easily change a resistor value, so we use a variable resistor. For example, we may want to change the resistor that controls the power sent to a LED, so we can easily make it brighter or dimmer. Often if we use a variable resistor, there is only a very narrow range that is useful. Continuing our example, sometimes we use several LEDs, and we use the variable resistor to set them all to the same brightness. In this case, the resistance range that sets the LED to be twice as bright as the the other LEDs, and the resistance range that sends so much power to the LED that it is permanently destroyed is even less useful. So we add a fixed resistor in series with the variable resistor -- the fixed resistor sets the minimum net resistance, no matter how we turn the knob on the variable resistor. In our example, the addition of the fixed resistor allows us to turn the variable resistor throughout its whole range, and the LED gets brighter and dimmer; without that resistor, a certain range of the knob on the variable resistor would allow so much power to go to the LED that it would be destroyed.
What effect if any does connecting a voltmeter across a resistor in a circuit have on the current through the resistor?
A very very tiny amount of the current that would normally flow through the resistor instead flows through the voltmeter, allowing it to make its measurement. For most purposes this very very tiny amount of current can be completely ignored.
When measuring the voltage across a resistor the reading is 0v what is the first step to locate the problem?
The resistor has gone to open ( or possibly short ) circuit. Remove ( if possible ) the resistor from the circuit and measure its stand alone resistance. If the resistor measures infinate then you need to replace it with whatever the circuit asks for. ie 10ohms, 15 ohms etc. Make sure you test the simple things first such as power supply and ensure that you are receiving power to at least one side of the resistor. If you are working on an electronic card then make sure you check your ' circuit paths ' you may have a burnt track. Test your continuity across your paths. Don't nescessarily concerntrate on the resistor itself it may not have power on it due to another component failure or circuit failure. Cheers.
Materials needed to make a resistor.?
carbon
What does manufacturing mean?
Manufacturing means making something. Some companies make shoes, some make surfboards, and some make computers. All of these things can be called manufacturing.
What does Cora-Texas Manufacturing make?
Cora-Texas Manufacturing produces sugar
Why resistors have tolerances?
Some design engineers that make electronic circuits specify tolerances in the resistors because a resistor that is too out of spec would not operate properly. A resistor with a brown band I believe is within 20%, a black is 10%, and gold is 5%. So if a resistor is rated at 3000 ohms, depending upon the band, it can vary a certain percentage. Resistors with the gold band I believe are called "precision resistors". The more "precision" the resistor is, the more it costs. To keep costs low, tolerances are sometimes included to alert the assembler that a precision resistor may not be necessary. For instance if a value of 3000 ohms can be within 20% then a cheap resistor may be used and is not critical in the circuit. The tolerances are introduced in manufacturing of resistors because practically, we can achieve 100% correct resistance. So, a tolerance range is indicated to make aware the users to select the proper resistor according to their application.
Can you make failure in a sentence?
We had a power failure due to the storm.
How do michigan make money?
By manufacturing
4 percent of its resistors are defective make to deliver 5000 resistor?
Make 5,209 of them.
Where is the AC fan speed resistor in a 1998 Buick Regal?
The resistor is mounted to the heater case on the passenger side of the vehicle. There is a hush panel that you will have to remove first. The resistor is mounted with three very small hex headed screws. My advise is to remove the one closest to you when you are under the dash, and only loosen the other two which are very hard to get at. Sometimes, you can't get to them at all, so you will need to bend the resistor down and pull towards you while rocking the resistor. It should pop out with some effort. While the resistor is out, loosen the two hard to reach screws just enough to make it easy to reinstall the new resistor, then install the resistor and the third screw. You shouldn't have to tighten the other two screws. Connect all related wiring that goes to the resistor and the blower motor. There is one other thing to worry about on these cars. There is a water deflector under the wiper cowl panel outside the car that can sometimes fall off. When this deflector/ weatherstrip falls off, it will allow water to hit the blower resistor and will cause it to fail prematurely. Make sure this is installed correctly to avoid a repeat failure. Russtech67
What is sensitivity training?
Sensitivity training is a type of training that is supposed to make a person more aware of their own prejudices and to become more sensitive to others. It is said that this type of training will make you a better person.
How do you isolate fault in a open resistor?
You need to first understand the way the resistor is "put together". There are various different types, and you didn't specify. For example, there are simple bulk resistors where everything in the electrical path lies on a straight line. In a wirewound resistor, the resistor element is wound in a spiral around a cylinder. Or you could be talking about a resistor in an Integrated Circuit (IC) or on a thick-film hybrid circuit. You could be talking about a small "chip" resistor that goes onto a PCB. You need to be more specific to get a more specific answer.The first thing you should determine is if the resistor is actually open, or if you simply have a bad connection to the resistor. Is it soldered to something? If so, use an ohmmeter equipped with pointed probes to check for connection on either side of both of the resistor's solder joints, if possible. If this is not possible (such as in the case of a surface mount "chip" resistor), you have to consider the solder joint as part of the resistor in the investigation.In fact, you should keep in mind that failure of a solder joint is MUCH more likely than simple failure of a resistor, unless the resistor has had too much current passed through it. Resistors tend to be mechanically more robust and reliable than solder joints.If the resistor was electrically overstressed (too much current, causing too much power dissipation/heat) the point of failure should be fairly obvious. There will be black, carbonized material at the failure point. You may need an optical microscope to see it, and it could be internal. There may be other external signs, such as bulging or discoloration that are not as obvious.If the resistor is not truly open but merely very high resistance, it may be possible to thermally image the fault location. Care must be taken to not pass through too much current and make the fault worse (unless you only care about the fault's location and not its cause).A high resolution x-ray can be used to image and find electrical opens in some types of resistors. It may also be possible to use more advanced tools such as Acoustic Tomagraphy, but that is rarely justified for using on a resistor that has become open. There are simpler, cheaper techniques that will give good results. The big advantages to x-ray and Acoustic Tomagraphy are that they can be done non-destructively.If it is a true electrical open, you generally expose the conductive element by stripping off the exterior chemically, or by cross-sectioning the device. Opens can then usually be spotted with simple optical microscopy. If the defect is too small, a Scanning Electron Microscope (SEM) can be used to image it. If one lead of the resistor is grounded, the un-grounded part of the resistor will quickly accumulate a charge and start to "glow" in the SEM, exposing the site of the open.Remember, if you couldn't verify that the solder connections to the resistor were OK, you have to consider them as possible points of failure in the analysis.
What is the Device in a circuit to make it harder for electricity to flow?
the device is a resistor
