The methods are listed below.
Low resistance measurement methods.
Carey foster bridge method 3 measurement of high resistance.
The four wire kelvin method of measurement is preferred for resistance values below 100 ω and all cropico milliohmmeters and microhmmeters use this method.
Also at this level standing.
Following are the methods employed for measuring a resistance whose value is in the range 1ω 100kω ammeter voltmeter method.
This is the most crude and simplest method of measuring resistance.
In the above picture r is the unknown resistor and v is a multimeter set to read millivolts.
1 measurement of low resistance.
The four wire kelvin method of measurement is preferred for resistance values below 100ω and all seaward milliohmmeters and microhmmeters use this method.
The dc potentiometer method of measurement of resistance is used for measuring the unknown resistance of low value.
These measurements are made using 4 separate wires.
2 wires carry the current known as the source or current leads and pass current through the rx.
Carey foster bridge method.
Kelvin method this method of measurement which avoids errors caused by wire resistance is called the kelvin or 4 wire method.
2 wires carry the current known as the source or current leads and pass current through the rx.
Kelvin double bridge method.
These measurements are made using 4 separate wires.
Obviously the multimeter is connected permanently as shown in picture.
This can be done by comparing the unknown resistance with the standard resistance.
The voltage drop across the known and unknown resistance is measured and by comparison the value of known resistance is determined.
Ohm meter method 2 measurement of medium resistance.
Low resistance measurement method basically the trick is to pass a stable known amount of current through the low value resistor and measure the voltage drop across it.
Special connecting clips called kelvin clips are made to facilitate this kind of connection across a subject resistance.
A low resistance measurement is typically a measurement below 1 000 ohm.
