Instrumentation Linearity Performance Test

This test applies to the following models:

  • P-Series Power Meters,
    Factory Recommended Variant    :

    N1911A

    N1912A

    N8262A

The Instrumentation Linearity specification describes the ability of the power meter’s data acquisition system to accurately measure the power sensor voltage. The specification acts as an additional uncertainty term expressed as a percentage of the measurement.

Linearity (that is, Normal Mode Instrumentation Linearity) is defined as:

where,

The voltages at the input are provided by an input signal with known relationship between values and enough different values to provide coverage of the transfer characteristics. This could be a DC voltage source with a measurement path to an external voltmeter. In our case we will choose to apply a sinusoidal waveform, with verifiable characteristics, and use the known relationship between phase and amplitude of a sinewave to determine the input values.

Required Equipment

Test Equipment

Recommended Model Number

Audio Analyzer

U8903B

Peak Power Meter Adapter

N1915A

Cable, XLR (m) to XLR (f), 2 m

U8903A-103
(U8903-61301)

BNC-cable

8120-2582

Connection Setups

Connections on power meters with rear panel options will differ than those in the illustrations below. Refer to the rear panel of the power meter for connector identification labels.

Channel A

Channel B