’ The column number of the data
’ "1" indicates the first data column ’ Total number of scans
’ Total number of scanned channels
’ Time interval in seconds between scans ’ Reading count in instrument memory
’ Store the string returned from instrument ’ List of channels included in scan
’ Delay between relay closure and measurement ’ Clear the spreadsheet

Chapter 7 Application Programs

Example Programs for Excel 7.0

Excel 7.0 Example: ScanChannels Macro

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This Excel Macro (Visual Basic) configures the 34970A for scanning with the 34901A,

34902A, or 34908A multiplexer modules. When this subroutine is executed, it will

scan 5 channels and display the readings on a spreadsheet. You can easily modify the

channels in the scan list, number of scans, channel delay, and scan delay. To make these

changes, modify the code in the section titled ’SET UP’. Note that you must have one of

the above modules installed in slot 100 for this program to run properly. You must also

have an GPIB interface card installed in your PC with the VISA or VTL library. ’""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

Option Explicit Sub ScanChannels()

Dim columnIndex As Integer

Dim numberScans As Integer Dim numberChannels As Integer Dim ScanInterval As Single Dim points As Integer

Dim replyString As String Dim scanList As String Dim channelDelay As Single Dim Channel As Integer Range("a1:ba40").ClearContents

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To change the GPIB address, modify the variable ’VISAaddr’ below.

VISAaddr = "9"

OpenPort

Open communications on GPIB

SendSCPI "*RST"

Issue a Factory Reset to the instrument

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SET UP: Modify this section to select the scan interval, the scan count,

and channel delay.

’ These are variables that are used to set the scan parameters

ScanInterval = 10

’ Delay (in secs) between scans

numberScans = 3

’ Number of scan sweeps to measure

channelDelay = 0.1

’ Delay (in secs) between relay closure and measurement

To delete channels from the scan list, modify the scan list string variable

’scanList’ below. To add channels to the scan list, modify ’scanList’ and then

configure the channel using the CONFigure command.

’scanList’ is the list of channels in the scan list; note that this does not have

to include all configured channels in the instrument.

scanList = "(@101,102,110:112)"

 

 

 

 

SendSCPI "CONF:TEMP TC,T,(@101)"

’ Configure channel 101

for temperature

 

SendSCPI "CONF:TEMP TC,K,(@102)"

’ Configure channel

102

for temperature

7

SendSCPI "CONF:TEMP THER,5000,(@103)"

’ Configure channel

103

for temperature

SendSCPI "CONF:VOLT:DC (@110,111,112)"

’ Configure three channels for dc volts

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SendSCPI "ROUTE:SCAN " & scanList

’ Select the list of channels to scan

SendSCPI "ROUTE:SCAN:SIZE?"

’ Query the number of channels in scan list and

numberChannels = Val(GetSCPI())

’ set variable equal to number of channels

SendSCPI "FORMAT:READING:CHAN ON"

’ Return channel number with each reading

SendSCPI "FORMAT:READING:TIME ON"

’ Return time stamp with each reading

Set the delay (in seconds) between relay closure and measurement SendSCPI "ROUT:CHAN:DELAY " & Str$(channelDelay) & "," & scanList

Continued on next page

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Agilent Technologies 34970A manual Excel 7.0 Example ScanChannels Macro, Dim columnIndex As Integer

34970A specifications

Agilent Technologies 34970A is a versatile data acquisition and measurement system that has gained popularity in various industries, including research and development, manufacturing, and education. The primary purpose of the 34970A is to offer an efficient solution for data collection, monitoring, and analysis, which can significantly enhance productivity and accuracy in testing applications.

One of the main features of the 34970A is its modular design, allowing users to customize the system according to their specific measurement needs. The mainframe can accommodate up to three plug-in measurement modules, which can include various types of measurements such as analog, digital, temperature, and frequency. This modularity provides flexibility for users to tailor the system to their requirements, making it highly adaptable to different applications.

Another notable characteristic of the Agilent 34970A is its impressive channel configuration. The system can support up to 120 measurement channels when fully configured, enabling extensive data acquisition without the need for multiple devices. This capability is essential for applications requiring simultaneous monitoring of multiple parameters or locations.

The 34970A utilizes advanced signal processing technologies to ensure high-accuracy measurements. The internal 6.5-digit resolution multimeter provides precise readings, while the device also supports various input types, such as thermocouples and RTDs for temperature measurements. The ability to perform mathematical functions, such as summation and averaging, on the acquired data further enhances its usability.

For data storage and management, the Agilent 34970A features built-in memory for storing up to 20,000 readings. Users can also easily transfer data to a PC through the RS-232 interface or GPIB (IEEE 488) for further analysis and reporting. Additionally, it offers the capability to program automatic data logging and scheduling of measurements, which streamlines the testing process and reduces manual intervention.

In terms of user interface, the 34970A is equipped with a large graphical display that provides clear visualization of measurement data and easy navigation through settings and options. The menu-driven interface makes it accessible for users of all skill levels, simplifying the setup and operation of the device.

Overall, the Agilent Technologies 34970A stands out for its modularity, high channel capacity, advanced measurement technologies, and user-friendly interface. As a reliable and efficient data acquisition system, it is well-suited for a wide range of applications, making it an essential tool for engineers and technicians looking to enhance measurement precision and efficiency.