Many applications require multiple channels of measurement. The Integra series products can accommodate up to 80 channels per Model 2700 and Model 2701 and up to 200 channels per Model 2750. For applications requiring more channels than one Integra series product can accommodate, multiple Integra series products are required.
The Revision C1 and later of the ExceLINX-1A package, a Microsoft Excel Add In, has the capability to control multiple Integra series products with the same spreadsheet. The following is a description on how to control more than one Integra series product with the ExceLINX-1A package. Describing each parameter in each task of ExceLINX-1A is beyond the scope of this technical note. For complete description and examples on the operation of ExceLINX-1A refer to the help feature in the package.
As an example of controlling multiple units with one software package we will consider the application of measuring the temperature of multiple IC devices in an environmental chamber. Each device must be "Temperature Cycled" for 48 hours. And each device requires a temperature monitor/sensor. In this case we will use thermocouples. The number of devices is 320 in one oven.
The Model 2750 with five Model 7708 modules would be a good choice for this application (the Model 2750 can hold up to five modules). Each Model 7708 module has 40 channels and there is a cold junction reference on the module for thermocouple (TC) measurements. This is a total of 200 channels per Model 2750. To achieve the 320 channels requirement, a second Model 2750 with additional 7708 modules is used. Three additional Model 7708 cards placed in the second Model 2750 would yield the 320 channels.
The software package ExceLINX-1A is used to control the channel closures and temperature measurements. ExceLINX-1A is operated from within the Microsoft Excel spreadsheet. The main control is a pull down menu (ExceLINX) on the main tool bar. All configurations start with the ExceLINX pull down menu. This application requires 320 channels of TC measurements. At this point the channels, scan list and data presentation all need to be configured.
Test System Configuration
There are several parameters to configure in order to control multiple Integra series products with one ExceLINX-1A package. The first parameter is the GPIB device address.
1. Set the device Address.
Each 2750 requires it's own unique address. One device is configured when the software is installed. A second device needs an address. The software needs to match this address. This is configured in the ExceLINX pull down menu with the "Configure Instruments" selection. In this procedure the address, driver and VISA resource are configured for a new device.
a. Select the Help tab and Show Wizard. This starts the Keithley Configuration Wizard.
b. Click on Next.
c. Select Add a Configuration. Click on Next.
d. For this application Select GPIB. Click on Next.
e. Select Appropriate GPIB card (e.g. GPIB0). Then click on Next.
f. Select appropriate GPIB address (e.g. 16). Click on Next.
g. Select the driver. In this application select KE Model 2700. Click on Next.
h. Click on Next to select the name.
i. Click on Finish to complete configuration.
j. Save and Close the Configuration Panel.
Configure Scanning DMM Channels
The next step is to set up the channels in the scan list for each device/instrument.
a. Pull down the ExceLINX menu and select Create then select Configure Scanning DMM Channels.
b. In the Instrument section on the Device line select the first device to be configured (e.g. GPIB0::16::INSTR)
c. In the channel scan list section select Enb(Enable) to ON. Then enter the desired scan list (e.g. 101-120) under List. This would be the first 20 channels in slot one of device GPIB0::16::INSTR.
d. Then on the same line select the remaining desired parameters (e.g. Function, Range, Math, Limits, etc.)
e. Repeat steps a through d for the second device. Select the appropriate channels in the scan list (e.g. 101-520).
Scan DMM Channels
The Scan process is now ready to be configured.
a. Pull down the ExceLINX menu and select Create, then Scan DMM Channels.
b. In the Trigger section select Reading Count of 10.
c. In the Trigger section select Sheet 1 for Data Location Worksheet.
d. In the Trigger section select row 1 for the first device/instrument.
e. Repeat step a through d for the second device/instrument. Except select row 15 for the second device/instrument.
Run both instruments
Each instrument needs to be started separately. This can be done from the ExceLINX menu or from the ExceLINX tool bar.
a. Pull down ExceLINX.
b. Select DMM Scan.
c. Select Start.
The instruments can run simultaneously. The scan for each instrument cannot be started at same time.
Select Sheet1 to monitor the data collection. This displays the data as it is being collected. In this example the timestamp, channel number and units are not enabled. Only the data is shown on Sheet1. To enable these parameters reconfigure them using the Scan DMM Channels task.
Some applications require more channels than one Integra series product can accommodate. Multiple units are necessary to increase the channel count. ExceLINX-1A can configure and operate multiple units.
Configuration includes setting a new address for each unit in the Keithley configuration panel. Each instrument requires configuration with a separate set up sheet (DMM CONFIG and DMM SCAN) in ExceLINX-1A.
Each configuration can run simultaneously, however, they cannot be started at the same time. The software trigger to start each configuration is sequential; this means start one configuration then start the other configuration.
As the configuration runs the data is shown in the spreadsheet. It can also be stored into a file for future analysis.