CONFigure:FRESistance
Syntax
CONFigure:FRESistance [{<range>|AUTO|MIN|MAX|DEF} [,{<resolution>|MIN|MAX|DEF}] , ] [(@<ch_list>)]
Description
First, this command resets all measurement parameters on the specified channels to their default values. Then, configures the channels for 4-wire resistance measurements but does not initiate the scan (channels in Bank 1 are automatically paired with corresponding channels in Bank 2). If you omit the optional <ch_list> parameter, this command applies to the internal DMM, independent of any channels or a 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.
Used With:
34921A Armature Multiplexer
34922A Armature Multiplexer
34923A Reed Multiplexer (differential mode only) *
34924A Reed Multiplexer *
34925A FET Multiplexer (differential mode only) *
* Series channel resistance must be taken into account for resistance measurements on this module.
Parameters
|
Name |
Type |
Range of Values |
Default Value |
|
<range> |
Numeric |
Expected value in ohms (ranges shown below). 100Ω (MIN) |
AUTO (autorange) |
|
<resolution> |
Numeric |
Desired resolution in ohms. |
0.000003 x Range (1 PLC) |
|
<ch_list> |
Numeric |
One or more channels in the form (@sccc). |
If <ch_list> is omitted, this command applies to the internal DMM. |
Remarks
If you omit the optional <ch_list> parameter, the configuration applies to the internal DMM, independent of any channels or a scan list (any existing scan list is not redefined). An error is generated if the internal DMM is not installed or is disabled.
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. The Analog Bus relays (numbered s911, s912, s913, etc.) on the multiplexer and matrix modules are ignored if they are included in a range of channels. An error will be generated if an Analog Bus relay is specified as the first or last channel in a range of channels.
You can allow the instrument to automatically select the measurement range using autoranging or you can select a fixed range using manual ranging. Autoranging is convenient because the instrument decides which range to use for each measurement based on the input signal. For fastest scanning operation, use manual ranging on each measurement (some additional time is required for autoranging since the instrument has to make a range selection).
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:]FRESistance:NPLC command to specify the desired integration time.
-
Autorange thresholds:
Down range at:
<10% of range
Up range at:
>120% of range
If the input signal is greater than can be measured on the selected range (manual ranging), the instrument gives an overload indication: "±OVLD" from the front panel or "±9.9E+37" from the remote interface.
For 4-wire resistance measurements, the instrument automatically pairs channel n in Bank 1 with channel n+20 in Bank 2 (34921A, 34923A, 34925A) or n+35 (34922A, 34924A) to provide the source and sense connections. For example, make the source connections to the HI and LO terminals on channel 2 in Bank 1 and the sense connections to the HI and LO terminals on channel 22 (or 37) 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>).
Since 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. In addition, if the Bank 2 channel was previously configured to be part of the active scan list (see ROUTe:SCAN command) and is then re-configured to be paired with a Bank 1 channel, an error will be generated and the previous scan list will be cleared. For example:
CONF:VOLT:DC (@1021) !Configure
Bank 2 channel for dc voltage measurements
ROUT:SCAN (@1001:1040) !Add
channels to scan list
CONF:FRES (@1001) !Generates
error and clears scan list
Four-wire measurements are not allowed on the multiplexer modules configured for the single-ended mode (see SYSTem:MODule:WIRE:MODE command).
For 4-wire 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 4-wire measurements on channel 4 in slot 3. 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 range (autorange) and resolution (1 PLC) are used for the measurement.
Note that for this 4-wire measurement, channel 4 in Bank 1 is automatically paired with channel 24 in Bank 2 (assumes 34921A).
CONF:FRES
(@3004)
ROUT:SCAN (@3004)
READ? (@3004)
Typical Response: +1.32130000E+03
The following command generates an error since you must always specify the paired channel in Bank 1 as the <ch_list> channel for 4-wire measurements (channel 36 is in Bank 2).
CONF:FRES (@4036) !Generates an error
The following program segment configures the instrument for 4-wire resistance measurements on channels 3 and 8 in slot 1. 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. The 1 kΩ range is selected with 1Ω resolution.
Note that for this 4-wire measurement, channel 3 is automatically paired with channel 23 and channel 8 is automatically paired with channel 28 (assumes 34921A).
CONF:FRES
1000,1,(@1003,1008)
ROUT:SCAN (@1003,1008)
INIT
FETC?
Typical Response: +4.27150000E+02,+1.32130000E+02
The following program segment configures the internal
DMM for a 4-wire measurement (no <ch_list> is specified). The READ?
command places the internal DMM 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 range (autorange) and resolution
(fixed at 6
CONF:FRES
!Applies
to the internal DMM
READ?
Typical Response: +2.93830000E+03
See Also
[SENSe:]FRESistance:OCOMpensated
SWEep:COUNt