Questions tagged [multimeter]
A multifunction measuring instrument used for measuring AC and DC voltage [V] and current [A] as well as resistance [Ω]. Many digital multimeters can also measure frequency [Hz], duty cycle [%], capacitance [F], temperature [°C], and/or other electrical or physical properties. Most are handheld; more expensive bench models are also available for applications requiring high precision.
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Current Measurement of a Brushless DC motor
I am trying to measure the current drawn by a brushless DC motor under load. This is to check if the propeller and the motor are a correct fit at the desired conditions (a range of rpm, say 0-8000rpm)....
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While Identifying Transistor terminals with Multimeter diode mode, why does B-E junction yields a slightly higher forward voltage then B-C junction?
I've learned that multimeter produces a small current in the diode mode and then measures the voltage drop across the diode. So a high resistance should produce a high voltage difference.
Since ...
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What would cause an AC multimeter reading to change if you reverse the probes?
I'm measuring the voltage in to a thermostat.
It's supposed to be AC.
When I measure wire1 and wire2 with black and red probes I get 0VAC
When I reverse the leads I get 1.8VAC
How can that even happen?...
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How does a multimeter measure small voltages without being connected to ground?
I have a multimeter powered by a 9 volt battery.
I put it in AC voltage mode that allows me to measure 0.001 volts.
I have the red probe connected and the black probe (common / ground) detached.
When ...
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No voltage difference between driven MOSFET gate and floating drain/source
I'm measuring the voltage of a discrete MOSFET using a multimeter. The gate is connected to the output of a logic circuitry, while drain and source are floating. The voltage difference between drain/...
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Error measuring the voltage with a multimeter?
When testing my batteries, I wanted to test the battery on my multimeter without taking it out because I wouldn't have other new 9v batteries if I did. But, it just displayed a 1 (which means an error)...
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Trying to understand (and mimic) the multimeter's interference with a circuit
I am trying to use a microcontroller to regulate the speed control of a sewing machine, rather than the foot pedal that normally serves this purpose. The pedal cord has 2 wires that connect it to the ...
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Best tool for measuring short duration voltage/current?
I'm reusing a watering timer (Melnor 4-port) by removing the circuitry and using only the latching solenoid-driven valves with my own microcontroller. I'd like to determine exactly how much voltage/...
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Measuring the resistance of an LED -> getting conflicting values
I couldn't find the resistance values for an LED so I tried to measure it and ended up much more confused than before:
I have a plain (red) LED and initially I used a multimeter to measure the ...
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UNI-T UT181A question: what is confidence interval used in the datasheet?
So the question is: https://www.batronix.com/pdf/uni-t/UT181A-Manual-English.pdf
The manual has
So if you are measuring perfect 50 Hz source you have resolution 0.001 Hz the values are in interval ...
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Determining if a multimeter will damage ICs - How to confirm?
I’m looking for a straightforward way to determine if a particular multimeter will damage sensitive electronics such as ICs.
Specifically, let’s say I have a Fluke 117 multimeter and I am trying to ...
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Capacitance on floating terminals of a multimeter
Why does a multimeter show some capacitance when its terminal are not connected to any capacitor?
My multimeter is showing 30pF. Does this imply that my multimeter is not calibrated properly or it is ...
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Why isn't tungsten used for multimeter probes?
Gold is considered the best multimeter probe tip (though disadvantages are
that it comes off easily when rubbed and is expensive) since its surface
hardly oxidizes when exposed to room-temperature air,...
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UT61E multimeter AC Voltage measurement issue
when i connect to AC 220V it start at 99 acv and drop to 70 or 60 which is wrong value for that AC..how can i fix this issue?
i cleaned VR2 with some alcohol, rotate it, the voltage changed to +350 ...
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Measuring current with a multimeter around a closed circuit [closed]
A question from physics lab:
Referring to the circuit you built to measure currents, what would happen if we completed our circuit with a wire and measured the current with the multimeter at the same ...
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