Keithley 3700 Series User Manual

Series 3700A System Switch/Multimeter Reference Manual Section 4: Basic DMM operation
3700AS-901-01 Rev. D/June 2018 4-33
For example, the following remote commands configure temperature function to a custom RTD and
assign it to a 10-channel scan list.
reset()
dmm.func=dmm.TEMPERATURE
-- or 3, or dmm.TEMP_FOURRTD, or 4
dmm.transducer= dmm.TEMP_THREERTD
-- dmm.fourrtd also supported
dmm.threertd=dmm.RTD_USER
-- allowed values are 0 to 0.01
dmm.rtdalpha= 0.003
-- allowed values are 0 to 1.00
dmm.rtdbeta= 0.105
-- allowed values are 0 to 5.00
dmm.rtddelta = 1.51
-- allowed values are 0 to 10,000
dmm.rtdzero= 125
-- default dmm.ON
dmm.offsetcompensation=dmm.OFF
dmm.configure.set("my_rtd_user")
dmm.setconfig("4001:4010", "my_rtd_user")
scan.measurecount=1
buf=dmm.makebuffer(20)
buf.clear()
buf.appendmode=1
scan.create("4001:4010")
scan.scancount=2
scan.execute(buf)
for x=1, buf.n do printbuffer (x,x,buf) end
channel.open("allslots")
Temperature equations
The following topics contain information you can use when making temperature measurements.
• Thermocouple equation (on page 4-33): Documents the ITS-90 inverse function polynomial and
the coefficients to calculate thermocouple temperature.
• Thermistor equation (on page 4-38): Documents the Steinhart-Hart equation, which is used to
calculate thermistor temperature.
• RTD equations (on page 4-39): Documents the Callendar-Van Dusen equation, which is used to
calculate the temperature versus resistance readings listed in the RTD reference tables.
Thermocouple equation
The Series 3700A uses the ITS-90 inverse function coefficients for the polynomial to calculate
thermocouple temperature. The Series 3700A measures the thermocouple voltage and then
calculates temperature (in °C) as follows:
t
90
= c
0
+ c
1
E + c
2
E
2
+ c
3
E
3
... c
i
E
i
Where:
• t
90
= The calculated temperature in °C.
• c
0
, c
1
, c
2
, c
3
... c
i
= The coefficients for the thermocouple type.
• E = The thermocouple voltage in microvolts (µV).
The coefficients for each thermocouple type are listed in the following tables.

Keithley 3700 Series Specifications

General

Brand	Keithley
Model	3700 Series
Category	Multimeter
Language	English