A forum member asked me for the resolution of the Keysight 34470A in the low Ohms reading.
So, I thought to make a comparison to measure this 1 mOhm resistor with a few different Ohm-Meters.
It seems that such low resistance is a challenge even for high end multimeters.
Keysight 3458A100 Ohm range
Bias current: 10 mA
Measurement: 0.00100 Ohm (movement between 0.00099 to 0.00101)
10 uOhm resolution
7 1/2 digits available
Keysight 34470A100 Ohm range
Bias current: 1 mA
Measurement: Seems to be out of calibration with a minus Ohm value
6 1/2 digits available
Keysight 34410A100 Ohm range
Bias current: 1 mA
Measurement: 0.0010 Ohm
100 uOhm resolution
1 nOhm ! resolution shown in Average Statistic mode (very unstable in all uOhm and nOhm digits)
6 1/2 digits available
Keithley DMM7510This is the 7 1/2 digit Keithley top of the line multimeter
1 Ohm range
Bias current: 10 mA
Measurement: 0.0010614 Ohm
100 nOhm resolution
100 pOhm ! resolution shown in Average Statistic mode
7 1/2 digits available
Keithley 2450 SMUThis is the 6 1/2 digit Keithley SMU
OHM-Mode2 Ohm range
Bias current: 100 mA
Measurement: 0.001118 Ohm
100 uOhm resolution
5 1/2 digits available
SMU-Mode20 mV range
Bias current: 1 A
Measurement: 0.001011 Ohm
1 uOhm resolution
6 1/2 digits available
Keithley 2460 SMUThis is the 6 1/2 digit Keithley SMU
OHM-Mode2 Ohm range
Bias current: 100 mA
Measurement: 0.001167 Ohm
1 uOhm resolution
6 1/2 digits available
SMU-Mode200 mV range
Bias current: 1 A
Measurement: 0.001000 Ohm
1 uOhm resolution
6 1/2 digits available