To Test Voltage Measurement Accuracy; Procedure - Agilent Technologies 54845B Manual

Table of Contents

To test voltage measurement accuracy

This test verifies the voltage measurement accuracy of the instrument. The measurement is made

using dual-cursor automatic measurement so that offset errors are not a factor.

A power supply provides a reference voltage to check voltage measurement accuracy. The actual

supply voltage is monitored for accuracy using a NIST-traceable voltmeter. A dc blocking

capacitor and a BNC short are used to filter any noise generated by the power supply (especially

at low voltages) so it does not appear at the oscilloscope input.

Specification

Only the dual-cursor specification is tested.

Single Cursor Measurement: ±(gain accuracy + offset accuracy + resolution/2)

Dual Cursor Measurement: ±(gain accuracy + resolution)

Gain Accuracy: ± 1.00% of full scale at full-resolution channel scale

Resolution: 8 bits, (0.4% of full scale without averaging); or

12 bits, (0.024% of full scale with 32 averages) at ful-resolution scale

Offset Accuracy: ±(1.00% of channel offset + 1% of full scale) at full-resolution scale

Equipment Required

Equipment

Critical Specifications

Power Supply

7 mV to 30 Vdc, 0.1 mV resolution

Digital Multimeter

Better than 0.1% accuracy

(DVM)

Cables (2)

BNC

Adapters (2)

BNC (f) to banana (m)

Adapters (2)

BNC tee (m)(f)(f)

Blocking capacitor

0.18

Shorting cap

BNC

Procedure

Connect the equipment.

See figure 3-4.

a Use a BNC-to-banana adapter to connect a BNC cable to the power supply.

b Connect a BNC tee to the other end of the cable and connect the tee to channel 1 of the

oscilloscope.

c Connect another BNC cable to the tee at the oscilloscope and connect a BNC tee to the

other end of the cable.

d Connect the blocking capacitor to the BNC tee and connect the BNC short to the blocking

capacitor.

e Connect a BNC-to-banana adapter to the same BNC tee and connect the adapter to the

DVM input.

Chapter 3: Testing Performance