Keithley 3730 User Manual

Series 3700
System Switch/Multimeter User's Manual Section 5:
Basic Digital Multimeter (DMM) Operation
Document Number: 3700S
-900-01 Rev. A / August 2007 5-
17
Resistance measurements
The Series 3700 uses the constant-current method to measure resistance ranges from 1 to
1M. The Series 3700 sources a constant current (I) to the resistance and measures the
voltage (V). Resistance (R) is then calculated (and displayed) using the known current and
measured voltage (R = V/I). For the 10M and 100M ranges, the ratiometric method is used to
measure resistance.
Basic resistance measurements
The Series 3700 can make resistance measurements from 0.1 to 120M. For resistances
>1k, the 2-wire (2) method is typically used for measurements. For resistances 1k, the
4-wire (4) measurement method should be used to cancel the effect of test lead (and channel
path) resistances.
Offset compensated ohms (OC+)
The presence of thermal EMFs (voltages) can adversely affect low-resistance measurement
accuracy. To overcome these unwanted offset voltages, you can use offset-compensated ohms
on the 1, 10, 100, 1k, and 10k ranges for the 4 function.
Dry circuit testing (DRY+)
For power and low-glitch resistance measurements requiring a low open-circuit voltage (20mV),
dry circuit ohms can be used on the 1, 10, 100, 1k and 10k ranges (maximum of
2.4k) for the 4 function.
Connections
Analog backplane connector (rear panel)
Connections for resistance measurements are shown below.

Keithley 3730 Specifications

General

Brand	Keithley
Model	3730
Category	Multimeter
Language	English