Chapter 4 Features and Functions

Voltage Measurement Configuration

Voltage Measurement Configuration

To connect voltage sources to the module’s screw terminals, see page 21.

This section contains information to help you configure the instrument for making voltage measurements. The instrument can measure dc and true RMS ac-coupled voltages on the measurement ranges shown below.

100 mV

1 V

10 V

100 V

300 V

Autorange

XW c

Normally, the instrument’s input resistance is fixed at 10 MΩ for all dc voltage ranges to minimize noise pickup. To reduce the effects of measurement loading errors, you can set the input resistance to greater 4 than 10 GΩ for the 100 mVdc, 1 Vdc, and 10 Vdc ranges.

M”x wv tzx tx 5

Input Resistance

Input Resistance

Input Resistance

Setting

100 mV, 1 V, 10 V ranges

100 V, 300 V ranges

 

 

 

Input R Auto OFF

10 MΩ

10 MΩ

Input R Auto ON

> 10 GΩ

10 MΩ

 

 

 

The instrument selects 10 MΩ (fixed input resistance on all

dc voltage ranges) when the measurement function is changed or after a Factory Reset (*RST command). An Instrument Preset (SYSTem:PRESet command) or Card Reset (SYSTem:CPON command)

wx change the input resistance setting.

Sctxt”: First, select the dc voltage function on the active channel. Then, go to the Mwtvxw menu and select 10 MΩ (fixed resistance for all dc voltage ranges) or >10 GΩ. g“x wxyt

” 87 _ Ω.

INPUT R >10 G

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HP 34970A manual Voltage Measurement Configuration, XW c, Mx wv tzx tx, 87 Ω