CONFigure:TEMPerature
CONFigure:TEMPerature
Syntax
CONFigure:TEMPerature {<probe_type>|DEF},{<type>|DEF}[,1[,{<resolution>|MIN|MAX|DEF}]] ,(@<scan_list>)
Description
These commands configure the channels for temperature measurements but do not initiate the scan. If you omit the optional <ch_list> parameter, this command applies to the currently defined scan list.
The CONFigure command does not place the instrument in the "wait-for-trigger" state. Use the INITiate or READ? command in conjunction with CONFigure to place the instrument in the "wait-for-trigger" state.
The following table shows which temperature transducers are supported by each of the multiplexer modules.
Module Thermocouple RTD 2-Wire RTD 4-Wire Thermistor 34901A Armature Multiplexer
Yes Yes Yes Yes 34902A Reed Multiplexer Yes Yes Yes Yes 34908A Armature Multiplexer (1-Wire) Not Recommended1 Yes No Yes
1With a one-wire multiplexer, even very small ground currents can introduce substantial measurement error.
Parameters
Name Type Range of Values Default Value <probe_type> Discrete {TCouple|RTD|FRTD|THERmistor|DEF}
TCouple <type> Discrete
For TCouple:
{B|E|J|K|N|R|S|T} For RTD {85|91} For FRTD {85|91} For THERmistor {2252|5000|10000}
For TCouple:
J For RTD 85 For FRTD 85 For THERmistor 5000 <resolution> Numeric The resolution in degrees Celsius, Fahrenheit, or Kelvin. The temperature scale in use is specified by the UNIT:TEMPerature command. 1 PLC <scan_list> Scan List One or more channels, as shown:
(@310) - channel 10 on the module in slot 300.
(@305:310) - channels 05 through 10 on the module in slot 300.
(@202:207,209,302:308) - channels 02 through 07 and 09 on the module in slot 200 and channels 02 through 08 on the module in slot 300.
This is a required parameter.
Remarks
- For temperature measurements, the instrument internally selects the range; you cannot select which range is used. In the command syntax, be sure to include "1" as shown for the <range> parameter (preceding the <resolution> parameter).
- For RTD and FRTD measurements, use "85" to specify a = 0.00385 or "91" to specify a = 0.00391. Note that this command also redefines the scan list. The default (DEF) type is "85" (a = 0.00385).
- When you specify a range of channels with this command, any channels that are invalid will be ignored (no error will be generated) but the first and last channel in the range must be valid for the selected function.
- For thermocouple measurements, the instrument internally selects the 100 mV range. For thermistor and RTD measurements, the instrument autoranges to the correct range for the transducer resistance measurement. Specify the paired channel in the lower bank (source) as the <ch_list> channel.
- Thermocouple measurements require a reference junction temperature (see [SENSe:]TEMPerature:TRANsducer:TCouple:RJUNction:TYPE command). For the reference junction temperature, you can use an internal measurement on the module's terminal block (34901A only), an external thermistor or RTD measurement, or a known fixed junction temperature. If you select an external reference, the instrument makes thermocouple measurements relative to a previously-stored RTD or thermistor measurement stored in the reference register.
- By default, a fixed reference junction temperature of 0.0 °C is used (see [SENSe:]TEMPerature:TRANsducer:TCouple:RJUNction command).
- If you select autoranging (by specifying "AUTO" or "DEF"), an error will be generated if you specify a discrete value for the <resolution> parameter. When autoranging is combined with a discrete resolution, the instrument cannot accurately resolve the integration time (especially if the input signal is continuously changing). If your application requires autoranging, be sure to specify "DEF" for the <resolution> parameter, or omit the parameter from the command and use the [SENSe:]TEMPerature:NPLC command to specify the desired integration time.
- Since this command resets all measurement parameters on the specified channels to their default values, be sure to send the CONFigure command before setting any other measurement parameters.
- For 4-wire resistance measurements, the instrument automatically pairs channel n in Bank 1 with channel n+10 in Bank 2 (34901A) or n+8 (34902A) to provide the source and sense connections. For example, make the source connections to the HI and LO terminals on channel 02 in Bank 1 and the sense connections to the HI and LO terminals on channel 12 (34901A) or 10 (34902A) in Bank 2.Specify the paired channel in Bank 1 (source) as the <ch_list> channel (channels in Bank 2 are not allowed in the <ch_list>).
- Because channels are automatically paired for 4-wire resistance measurements (see previous Remark), attempts to re-configure the paired channel in Bank 2 will result in an error. For example:
CONF:VOLT:DC (@105) !Configure Bank 2 channel for DC voltage measurements
ROUT:SCAN (@101:110) !Add channels to scan list
CONF:FRES (@101) !Generates error and clears scan list
- For 4-wire RTD measurements, the instrument automatically enables the autozero function.
- The *RST command will clear the scan list and set all measurement parameters to their factory settings. The Instrument Preset (SYSTem:PRESet command) will not clear the scan list; however, this command will clear reading memory and all stored statistical data.
Examples
The following program segment configures the instrument for B-type thermocouple measurements on channel 04 in slot 300. The READ? command places the instrument in the "wait-for-trigger" state, scans the channel once, and then sends the reading to reading memory and the instrument's output buffer. The default resolution (fixed at 6
CONF:TEMP TC,B,(@304)
ROUT:SCAN (@304)
READ?
Typical Response: +3.65640000E+01
The following program segment configures the instrument for 5 kΩ thermistor measurements on channels 03 and 08 in slot 100. The INITiate command places the instrument in the "wait-for-trigger" state, scans the channels once, and stores the readings in memory. The FETCh? command transfers the readings from reading memory to the instrument's output buffer. This 2-wire measurement is made with 0.1
CONF:TEMP THER,5000,1,0.1,(@103,108)
ROUT:SCAN (@103,108)
INIT
FETC?
Typical Response: +2.47150000E+01,+3.12130000E+01
The following program segment configures the current scan list for a 2-wire RTD measurement (no <ch_list> is specified). The READ? command places the instrument in the "wait-for-trigger" state, initiates a trigger, and then sends the reading to reading memory and the instrument's output buffer. The default resolution (fixed at 6
CONF:TEMP RTD,85 (@203)
READ?
Typical Response:+2.12320000E+01
See Also
[SENSe:]TEMPerature:TRANsducer:FRTD:RESistance[:REFerence]