Four-Wire Ohms Measurement; Ac Voltage Measurement (1910Ac Option) - Keithley 192 Instruction Manual

Figure 4-4. Resistance Measurements
4.9 FOUR-WIRE OHMS MEASUREMENT
For 4-wire measurements. connect the sense leads to the
circuit to be measured and to the fi SENSE terminals on the
Model 192 (see Figure 4-5). This arrangement eliminates the
error due to the voltage drop ecross the current-carrying
leads. Accurate, high resolution ohms measurements are
obtained using 4wire connections.
Four-wire ohms measurements are recommended when
utilizing the .2k. 2k. or 20k0 range. Maximum test lead
resistance for 4-wire ohms measurement is given in table
4-4.
Table 4-4. Maximum Four-Wire Test Lead Resistance
Range
.2k
2k
20k
200k
Lead
Resistance+
70
220
700
2200
2000k
7oon
20M
22000
"Maximum resistance per lead for en additional 1 digit error
et 6K digits.
Figure 4-5. Four-Wire Resistance Measurement
4.10 AC VOLTAGE MEASUREMENT II910 AC Option)
With the Model 1910 option, the Model 192 reads AC
volteges from 1OpV digit to 1OOOV. The instrument is
average responding and is calibrated to the root mean
sauare value of e sine weve. with a freauencv span of 20Hz
to 100kHz.
INPUT IMPEDANCE: 2MR shunted by less than 5OpF
Figure 4-6. AC Voltage Measurements