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This depends on the type of resistor. Carbon composition and metal film resistors typically will burn open, carbon film types can short.
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What is the reason for putting a voltage rating on resistors?
Due to the physical construction and size of the resistor, at a certain voltage, the insulation will break down and the applied voltage will arc over. This is generally bad. Operating the resistor within its voltage rating will prevent this failure mode.
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 difference between a CB amplifier and CE and emitter-follower?
I think you mean a common emitter amplifier, which is an amplifier of voltage. Emitter-follower or common collector amplifiers are used to match impedances, or to amplify power or current. The emitter-follower is a type of common emitter circuit that has a resistor between the emitter and ground. The output signal is taken from the point between the emitter and its resistor.
A common cause of failure of electronic circuit boards is due to?
dry solder joints
Why resistor should disconnected from the circuit when measured the value of resistor?
if not disconnected you will measure the resistance of the circuit in parallel with the resistor.
Why does my 2003 trailblazer blower motor work on and off what could it be?
It can be a few different things but the most common failure is the blower motor resistor. If you visit our enthusiasts forum we can help you track it down quickly. www.trailvoy.com
What is the most common reason for graft failure?
The most common reason for graft failure is the formation of a hematoma, or collection of blood in the injured tissues.
Your heat and air only work in the high position?
your blower motor resistor is most likely failing. sometimes that's an indication of a failing blower motor, but typically, it's a resistor module failure
What is the most common reason for failure to obtain federal assistance even when the impact significant?
The most common reason for failure to obtain federal assistance is lack of adequate documentation.
Is moisture the most common reason for paint failure?
True
How common is failure to diagnose?
Failure to diagnose, unfortunately, is one of the most common forms of medical malpractice in the U.S. The most common conditions that have been misdiagnosed are Toxoplasmosis, sleep disorders, Otosclerosis, extra nipples and Osteoporosis.
What is the reason of car hvac blower resistor failure?
too much debries
What is the most common reason for relationship failure?
honesty,money, sex
What is most common source of business system failure is?
Data quality
Blower motor resistor in 2005 trailblazer is melted as is the male wiring harness that plugs into it. Is resistor the only cause of problem and how can I fix the wiring harness or must I buy new one?
The blower motor resistor is the common failure. It comes with the wires attached that plug directly to the blower motor itself. If there is another wiriing harness that is damaged then you will have to buy it too. The resistor failure has been linked as the only cause of the melted wires other than the blower motor itself. The motor can be tested with 12v power to it and it should run on high speed when tested.
Where is the blower motor resistor on 1988 Mazda B2200?
On the 88, remove the glove box by removing all the screws you see when you open the glove box door. You will see a 4 wire connector off to the right. It is plugged into the resistor. This is a common failure when any of the lower speeds of the blower motor fan don't work (high speed is not affected by the resistor).
Why does my blower fan run at all speeds except max Like the opposite of the normal resistor failure?
wiring fault. at max speed the resistor is bypassed
