[SENSe:]TEMPerature:NPLC

34980A

[SENSe:]TEMPerature:NPLC

Syntax

[SENSe:]TEMPerature:NPLC {<PLCs>|MIN|MAX|DEF} [, (@<ch_list>)]

[SENSe:]TEMPerature: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.

The following table shows which temperature transducers are supported by each of the multiplexer modules.

 

Thermocouple

RTD
2-Wire

RTD
4-Wire

Thermistor

 

34921A
Armature
Multiplexer

 Yes1

Yes

Yes

Yes

 

34922A
Armature Multiplexer

Yes2

Yes

Yes

Yes

 

34923A
Reed Multiplexer
(2-Wire)

Yes2,3

Yes4

Yes4

Yes5

 

34923A
Reed Multiplexer
(1-Wire)

Yes2,3

Yes4

No

Yes5

 

34924A
Reed Multiplexer

Yes2,3

Yes4

Yes4

Yes5

 

34925A
FET Multiplexer
(2-Wire)

Yes2

No

Yes5

No

 

34925A
FET Multiplexer
(1-Wire)

Yes2

No

No

No

 

1 Optional 34921T Terminal Block is required for thermocouple measurements with built-in internal reference junction.
2
A fixed or external reference junction temperature is required for thermocouple measurements with this module.
3
Impact of higher offset voltage specification (< 50 µV) must be taken into consideration.
4
1 kΩ or higher range used unless 100Ω series resistors are bypassed on module.
5
10 kΩ or higher range used for loads over approximately 300Ω due to series resistance of FET channels.

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

  • Only the integral number of power line cycles (1, 2, 10, 20, 100, or 200 PLCs) provide normal mode (line frequency noise) rejection.

  • 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.

  • 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:]TEMPerature: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?, and [SENSe:]TEMPerature:NPLC commands disable the aperture mode (these commands select an integration time in number of power line cycles). You can use the [SENSe:]TEMPerature: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:]TEMPerature: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.

TEMP:NPLC 0.2,(@1003,1013)

The following query returns the integration time settings on channels 3 and 13 in slot 1.

TEMP:NPLC? (@1003,1013)
TEMP:APER:ENAB?  !Verify that aperture mode is disabled ("0")

Typical Response:

+2.00000000E-01,+2.00000000E-01
0

See Also

CONFigure:TEMPerature

[SENSe:]TEMPerature:APERture

[SENSe:]TEMPerature:APERture:ENABled?