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-
43
4. Set THERMO device attributes:
 Turn the wheel to scroll to the "THERMO" menu item and press the ENTER key.
 Turn the wheel to scroll to the "THERMISTOR" temperature connection and press the ENTER
key.
 Turn the wheel to select desired resistance (2252, 5000, or 10000) and press the ENTER
key.
5. Press the EXIT key twice to leave the "TEMP ATTR MENU."
Also see bus command dmm.thermistor for more information on setting thermistor measurement
attributes.
RTDs (Resistance Temperature Detector)
For 4-wire resistance temperature detectors (RTDs) the temperature measurement range is -
200°C to 630°C (0.01°C resolution). The Series 3700 supports 4-wire RTD types including:
PT100, D100, F100, PT385, and PT3916. A USER type is also available to modify RTD
parameters, such as the resistance at 0°C. Like the other supported 4-wire types, the USER
type can be enabled from the front panel, but the settings can only be changed using remote
programming.
The RTD has a metal construction (typically platinum). The resistance of the RTD changes with
change in temperature. The Series 3700 measures the resistance and calculates the
temperature reading. When using default RTD parameters, the resistance of the RTD will be
100 at 0°C.
Of all the temperature transducers, the RTD exhibits the most stability and linearity. By default
the Series 3700 performs the 4-wire measurement using offset-compensated ohms, which
provides the most accurate way to measure the low resistance of the RTD. For faster RTD
measurements when the most accurate measurements are not required, offset-compensation
may be disabled for 3-wire or 4-wire RTD measurements.
Use of a 3-wire RTD requires a special math capability to compensate for lead resistance on the
3rd wire. As for 3-wire RTDs, the Series 3700 supports RTD types including: PT100, D100,
F100, PT385, and PT3916. A USER type is available to modify RTD parameters, such as the
resistance at 0°C. Like the other supported 3-wire types, the USER type can be enabled from
the front panel, but the settings can only be changed using remote programming.
3-wire RTD connections
Shown below are 3-wire RTD connections to the Series 3700. For a 3-wire RTD capable 40-
channel switching module, paired channels are used to perform the 3-wire measurement. For
example, the two input leads of the RTD are connected to a primary channel (1 through 20),
while only the LO sense lead is connected to its paired channel (21 through 40)(see Note).
Channel 1 is paired to Channel 21, Channel 2 is paired to Channel 22, and so on.
NOTE The HI sense of the paired channels are not used (3-wire RTD).

Keithley 3730 Specifications

General

Brand	Keithley
Model	3730
Category	Multimeter
Language	English