Keithley 3700A Series Reference Manual

Series 3700A System Switch/Multimeter Reference Manual Section 4: Basic DMM operation
3700AS-901-01 Rev. D/June 2018 4-29
Thermistor measurement through the remote interface
This sample remote code configures a thermistor type 2252 and assigns it to a 4-channel scan list.
reset()
dmm.func=dmm.TEMPERATURE
dmm.transducer= dmm.TEMP_THERMISTOR -- or 2
dmm.thermistor=2.252e3
dmm.units=dmm.UNITS_FAHRENHEIT -- or 4
dmm.configure.set("my_thermist")
dmm.setconfig("4011:4014", "my_thermist")
scan.measurecount=1
buf=dmm.makebuffer(20)
buf.clear()
buf.appendmode=1
scan.create("4011:4014")
scan.scancount=5
scan.execute(buf)
for x=1, buf.n do printbuffer (x,x,buf) end
channel.open("allslots")
Also see remote command dmm.thermistor (on page 11-229) for more information on setting
thermistor measurement attributes.
RTDs (Resistance Temperature Detectors)
Of all the temperature transducers, the resistance temperature detector (RTD) exhibits the most
stability and linearity. The Series 3700A supports 3-wire and 4-wire RTD types of:
• PT100
• D100
• F100
• PT385
• PT3916
A USER type is also available to modify RTD parameters, such as the resistance at 0 °C. The USER
type can be enabled from the front panel, but the settings can only be changed using remote
programming.
For 4-wire RTDs, the temperature measurement range is –200 °C to 630 °C (0.01 °C resolution).
The RTD has a metal construction (typically platinum). The resistance of the RTD changes with
change with temperature. The Series 3700A measures the resistance and calculates the temperature
reading. When using default RTD parameters, the resistance of the RTD will be 100 Ωat°C.
By default, the Series 3700A 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 4-wire RTD measurements.
Use of a 3-wire RTD requires a special math capability to compensate for lead resistance on the third
wire.
For information about temperature equations, see Temperature equations (on page 4-33).

Keithley 3700A Series Specifications

General

Brand	Keithley
Model	3700A Series
Category	Multimeter
Language	English