In using the multimeter to measure voltage/current, 2 terminals are required.But why voltage measurement using the oscilloscope requires only 1 terminal (i.e. the hook)?
2006-07-31 02:32:12 · 5 answers · asked by のうる 1 in Science & Mathematics ➔ Engineering
The fact that the instrument you mention is an oscilloscope is irrelevant. You are using it as a voltmeter.
Any voltmeter has two test leads, both of which need to be connected across the voltage to be measured.
In the case of an oscilloscope one of those leads is usually (but not always - there are special cases) connected to the instrument's chassis and to earth.
If you measured voltage without having the earth clip of the probe connected to the circuit being tested then that connection was being made through the earth - to which both items were obviously connected.
This is not safe practice - but that's your business.
Dodo's "Voltage means the difference of power level (sic) between 2 points..."
No it doesn't.
Voltage is the potential difference between two points.
2006-07-31 09:50:51 · answer #1 · answered by dmb06851 7 · 2⤊ 2⤋
Because on an o'scope the straight line equals zero volts so if you are measuring DC the distance the line moves from the center equals the voltage and if you are measuring AC you have to use the "peak to peak" voltage. An o'scope doesn't require current to flow through the circuits to move a meter needle. The presence of the electric potential is interpreted by the already powered up internal circuitry as it is compared to an internal standard that is visually represented by the straight line across the screen.
2006-07-31 02:55:52 · answer #2 · answered by Martin S 7 · 0⤊ 0⤋
It requires 2 leads to go to the terminal of the scope.
If you don't use 2 leads then you've got the scope set up some other way and you're only measuring the voltage relative to the scope's ground.
2006-07-31 02:36:47 · answer #3 · answered by Anonymous · 0⤊ 0⤋
To get an accurate reading you need to hook up the ground lead on the probe to a reference point in the circuit, otherwise you are going to see NOISE!. So it really does require 2 "leads" just like a multimeter.
2006-07-31 02:44:27 · answer #4 · answered by justme 7 · 0⤊ 0⤋
I didn't know that...
Voltage means the difference of power level between 2 points... The other terminal should be there (as you have X & Y axis)
2006-07-31 02:36:31 · answer #5 · answered by toon 5 · 0⤊ 0⤋