[SENSe:]FRESistance:NPLC
Syntax
[SENSe:]FRESistance:NPLC {<PLCs>|MIN|MAX|DEF} [, (@<ch_list>)]
[SENSe:]FRESistance:NPLC? [{(@<ch_list>)|MIN|MAX}]
Description
This command sets the integration time in number of power line cycles (PLCs) on the specified channels. Integration time affects the measurement resolution (for better resolution, use a longer integration time) and measurement speed (for faster measurements, use a shorter integration time). If you omit the optional <ch_list> parameter, this command applies to the internal DMM, independent of any channels or a scan list.
Used With:
34921A Armature Multiplexer
34922A Armature Multiplexer
34923A Reed Multiplexer (differential mode only)
34924A Reed Multiplexer
34925A FET Multiplexer (differential mode only)
Parameters
|
Name |
Type |
Range of Values |
Default Value |
|
<PLCs> |
Discrete |
{0.02|0.2|1|2|10|20|100|200} MIN = 0.02 PLC, MAX = 200 PLC |
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.
Since 2-wire and 4-wire resistance are related functions, changing a measurement parameter for one function will also change the corresponding parameter for the other function (see [SENSe:]RESistance:NPLC command).
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>).
Four-wire measurements are not allowed on the multiplexer modules configured for the single-ended mode (see SYSTem:MODule:WIRE:MODE command).
Only the integral number of power line cycles (1, 2, 10, 20, 100, or 200 PLCs) provide normal mode (line frequency noise) rejection.
Setting the integration time also sets the resolution for the measurement. Click here to see the relationship between integration time, measurement resolution, number of digits, and number of bits.
The specified integration time is used for all measurements on the selected channels. If you have applied Mx+B scaling or have assigned alarms to the selected channel, those measurements are also made using the specified integration time. Measurements taken during the Monitor function also use the specified integration time.
You can also set the integration time by specifying an aperture time (see [SENSe:]FRESistance:APERture command). However, note that specifying integration time using NPLCs executes faster and offers better noise rejection characteristics for values of NPLC greater than 1.
The CONFigure, MEASure?, [SENSe:]FRESistance:NPLC, and [SENSe:]FRESistance:RESolution commands disable the aperture time mode (these commands select an integration time in number of power line cycles). You can use the [SENSe:]FRESistance:APERture:ENABled? command to query whether the aperture mode is currently enabled or disabled.
The instrument sets the integration time to 1 PLC after a Factory Reset (*RST command). An Instrument Preset (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command) does not change the setting.
Return Format
The query command returns the integration time in the form "+1.00000000E+00" for each channel specified. Multiple responses are separated by commas. Note that if the aperture mode is currently enabled (see [SENSe:]FRESistance:APERture:ENABled? command), the value returned will represent the previous value specified, not the actual integration time.
Examples
The following command set the integration time to 0.2 PLCs on channels 3 and 13 in slot 1. For this 4-wire measurement, the instrument automatically pairs these channels in Bank 1 with the corresponding channels in Bank 2.
FRES:NPLC 0.2,(@1003,1013)
The following query returns the integration time settings on channels 3 and 13 in slot 1.
FRES:NPLC? (@1003,1013)
FRES:APER:ENAB? !Verify
that aperture mode is disabled ("0")
|
Typical Response: |
+2.00000000E-01,+2.00000000E-01 |