0
Is a capacitor a device specifically designed to measure currents?
Wiki User
∙ 17y ago
No, a capacitor is a device that resists the change in electrical potential. It will take and hold a charge based on the value of the capacitor. It's most commonly used to "smooth" direct current or to pass a signal through a wire while passing very little current. There are some interesting circuits produced using capacitors, especially since the capacitors have so many unique properties.
Wiki User
∙ 17y ago
Add your answer:
Earn +20 pts
Can DC ampere be measured with AC amp meter?
No. The ammeter must be designed to measure DC. Some clamp-on ammeters are designed to measure both AC and DC.
What is conductometer?
A conductometer (conductivity meter) is an instrument designed to measure the electrical conductivity.
How do I test a capacitor when I cannot remove it out of circuit?
You cannot. It must be taken out of the circuit and then tested on its own.That's not 100% true because, if it has wires at its ends, you can cut through one wire with an appropriate tool and then test the capacitor "out of circuit". If the capacitor is ok you can then re-join the two cut wire ends by applying a blob of solder carefully. (But, to avoid damaging the capacitor, use a suitable heat sink to shield the body of the capacitor from the heat of the soldering iron.)With direct current a capacitor also works like a special type of resistance. Whilst being charged up, it will show low resistance. As it slowly (or quickly) charges, the resistance will grow larger and larger. Whenever I repair circuitry and I have doubts about a capacitor (in the uF area) I simply use my multimeter on its Ohms setting. If a capacitor has shorted, then the result will be 0 Ohm. If the capacitor is working, or partially working, the resistance will gradually increase until it is out of range of the multimeter.Use an ohm-meter first to test the on-board capacitor and then use it to test a similar capacitor off-board, to see if the results sort of match up.Most often they will not match completely as on-board you also measure the effect of all other components connected into circuit with the capacitor. It might point you in the right direction though.On a separate thought, if you really cannot remove it, or disconnect one of its connections, then why test it at all? If it really can't be removed to replace it, then it makes no sense to test it!A capacitor can be tested using multimeter without removing it from circuit. but in order to check it, its polarities should be noted and then keep the positive terminal of multimeter on positive of capacitor and negative terminal on negative. It is vital to note that the readings will be affected by the remainder of the circuit. To test for capacitor function in circuit demands a good understanding of the circuit operation.Of course there are ways to test capacitors, both in circuit and out. While a truly accurate test involved taking the cap out of circuit, a basic test can certainly be done in circuit.Out of circuit, one can either connect to a VM, or better yet, an oscilloscope, and measure the time for voltage to decay to zero across the capacitor. This time should equal the time given by the equation for the time constant, and is dependant on the values associated with that particular capacitor.For RC circuits, this equation equals:τ = R × C. It is the time required to charge the capacitor, through the resistor, to 63.2 (≈ 63) percent of full charge; or to discharge it to 36.8 (≈ 37) percent of its initial voltage. These values are derived from 1 − e − 1 and e − 1 respectively.It is important to keep in mind that one must apply a voltage across the capacitor at its rated value. Thus, if it is a 400V capacitor driving a tube amp, for instance, it must be driven at around 400V. Driving it at 12V will lead to useless results.The only proper way to check for a capacitor value and or leakage is with a proper test bridge: set it to the capacitor's DC rating with it removed from the circuit completely. Any other way is just waste of time.Additionally, a common in-circuit test for a electrolytic capacitor is to measure its Equivalent Series Resistance (ESR) which can be done with an ESR meter. This is a quick and easy way to locate failing electrolytic capacitors, especially in power supply circuits.An effective method of testing any component in-circuit is with an in-circuit curve tracer. If you have an oscilloscope with X-Y input mode you can easily build one of these on your own. They do take some getting used to before you can use it effectively and are most useful for good board vs. bad boardcomparison.
What is the var meter?
A VAR Meter is used to measure Reactive Power in AC Circuits - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q". A VAR Meter is used to measure Reactive Power in AC Circuits - Pure reactive components dissipate zero power, which makes sense in a DC circuit, as a capacitor passes no DC current and an inductor displaces no voltage. Yet, in an AC circuit, the reactive components "seem" to dissipate power, as current passes through the capacitor and the inductor sees a voltage drop. This counterfeit power is called "reactive power" and is measured not in Watts, but in VARs (Volt-Amps-Reactive). Its mathematical formula symbol is "Q".
Why is it called a watch?
CAN BE EXPLAINED IN A SIMPLE MANNER: 1. WATCH - A TIMEPIECE TO MEASURE TIME THAT YOU CAN WATCH ANY TIME AND THAT IS WORN IN THE BODY- eg. WRISTWATCH, RINGWATCH, POCKETWATCH, PENDANTWATCH. 2. CLOCK - AN INSTRUMENT TO MEASURE TIME WITH A BELL(ORIGIN) OF WORD. OPPOSITE TO WATCH WHICH IS NOT WORN AND USUALLY YOU WILL JUST STARE TO READ TIME. 3. TO PROPERLY READ TIME BETWEEN THE 2 TIMEPIECES FOR EXAMPLE ITS 8 A.M. NOW - HERE'S HOW A. USING A WATCH THE PROPER READING SHOULD BE - 8 O' WATCH B. USING A CLOCK THE PROPER READING SHOULD BE - 8 O' CLOCKIS THIS A GOOD LOGIC OR A GOOD JOKE?
What is the difference between capacitor and capacitance?
A capacitor is a device that stores an electrical charge, or if you prefer- resists any change in voltage applied to it. Capacitance is a measure of the size or ability of a capacitor to do that. This is the Farad
What do you measure currents in?
Currents are measured in amps being I
How are ocean currents measured?
In the unit that they measure ocean currents.
How do you measure the resistance of the capacitor?
A: Nobody can with an VOM
Why is there a C in the equation for a discharging capacitor?
The C represents the capacitance (in farads) of the capacitor. It is a measure of how much charge a capacitor can hold. This is needed to know how much energy the capacitor is holding.
How are the terms capacitor and capacitance related?
Capacitor is the name of the device and capacitance is a measure of farads in the capacitor. Capacitance is the capacity for storing charge in the capacitor as measured in farads, micro farads or millifarads.
What instrument measures small currents?
A galvanometer is used to measure small currents.
What is the unit of measure of capacitor?
Capacitors are measured in Farads or microfarads.
Flow meters are not used to measure bottom currents why?
Bottom currents move too slow.
A farad is a measure of what?
The Farad is a measure of how much electric charge is accumulated on the capacitor. Named after Michael Faraday
What is the function of vernier calliper?
It's designed to measure short distances more accurately than a ruler or tape measure, specifically the outside or inside opposing faces of an object. An example of it's use is to measure the outside diameter of a pipe.
What does a swallow float measure?
it checks ocean currents
