Digital Multimeter HDM3055 Series Manual

WisdomAugust

Histogram

The histogram shows measurement data as a graphical representation of the distribution of measurement

data. Data is grouped in bins represented by vertical bars in the histogram display.

NOTE Autoranging can adversely affect the histogram display when measuring repetitive signals spanning

multiple ranges. To avoid this, select a fixed range when using the histogram display.

WisdomAugust

Pressing the key, followed by the Display softkey allows you to select the display type:

Binning

The Binning softkey allows you to either let the instrument control how the histogram is binned (automatic binning),

or to manually specify the binning parameters with the Bin Settings softkey. Changing any binning parameter,

or switching between automatic and manual binning, will automatically start the histogram over with new data.

WisdomAugust

For Binning Auto, the algorithm starts by continuously readjusting the histogram span based on the

readings coming in, completely re-binning the data whenever a new value comes in outside of the

current span. After acquiring a large number of readings, a new reading outside of the range causes

the bins to be compressed by a factor of two such that the new bin range will cover the new reading.

The number of bins shown is a function of the number of readings received: 0 to 100 readings = 10 bins,

101 to 500 readings = 20 bins, 501 to 1000 readings = 40 bins, 1001 to 5000 readings = 100 bins,

5001 to 10000 readings = 200 bins, >10000 readings = 400 bins.

For Binning Manual, you can set number of bins to 10, 20, 40, 100, 200, or 400. You can specify the

bin range as either Low and High values, or as a Span around a Center value. For example, the

histogram range shown above (from -5 to 4 V) could be specified as a Low of -5 V and a High of 4 V,

or a Center of - 0.5 V and a Span of 9 V.

WisdomAugust

The Outer Bins softkey displays two additional bins, for readings above and below the bin range.

For example, this image shows the Outer Bins softkey set to Off.

WisdomAugust

The image below adds the outer bins to the display. The relatively large number of readings above

the bin range (the cyan bar) causes the bars within the bin range to shrink.

WisdomAugust

The main histogram menu includes a Cumulative softkey that hides or shows a line representing

the cumulative distribution of the histogram data. Note that this line represents all of the data only

when the outer bins are shown; if the outer bins are not shown, the outer bin data is not represented

in the line. The cumulative distribution line always goes from 0 to 100% on the vertical scale,

regardless of the histogram’s scale.

WisdomAugust

The final button on the histogram menu, Clear Readings, clears reading memory and starts a new

histogram.

Histogram Data

The graphic below shows a histogram of frequency measurements. Data is displayed on the left side

of the histogram. In the graphic below, reading from top left downward:

l 3.00000 kHz - present measurement value.

l 105 - Number of samples in the largest bin.

l 17.5% - Percentage of samples in the largest bin.

l Total 599 - Total number of samples.

l # Bins 20 - Total number of bins.

l 0, 2.5k, 5k - (Below the histogram) Range of frequency values.

WisdomAugust

Histogram with Statistics

Showing statistics (Shift > Math > Statistics) is particularly useful for the histogram display. For example,

in the graphic below, the thick blue line is the average, and each thin blue line represents one standard

deviation from the average.

WisdomAugust

Utility Menu - Introduction

The [Utility] key is the shifted [Display] key:

[Utility] provides the following features:

Store and Recall State and Preference Files

Manage files, including creating screen shots

Configure LAN (optional on HDM3065B), GPIB (optional on HDM3065H), and SCPI

Perform instrument self-tests and firmware update functions

Configure the instrument's date and time and various user settings

WisdomAugust

Utility - Autocalibration  

Autocalibration compensates for drift caused by time and temperature changes in DC voltage and resistance

measurements, and adjust some aspects of other measurement functions.

To quickly perform autocalibration without editing the cal string message, press Shift > ACAL (Up Arrow) key.

Use the procedure below to use menus and softkeys to edit the cal string message and perform autocal

Step 1: Press Utility on the front panel.

Step 2: Press the Test/Admin softkey: