Chromatography Forum

Hello,

is it possible to start runs in EZ Chrom 3.1.7 with an external program?
I need to do some calculations with the exported ascii-file and - depending on the results - repeat a run.
Is the Automation Toolbox a must for this task or is there any other option?

Thank you!

Slaven,

Since you are using an external program there is no other way to do this other than the Automation Interface.

If you would want to attempt this from within EZChrom:
1. Write a custom parameter script that "decides" whether run is within limits.
2. Use the outcome of the Custom Parameter to influence the System Suitability check
3. Use the Smart Sequence to re-run the sample if the System Suitability fails.

JW
Applied Instruments
http://www.applied-instruments.com

Hello JW,

thank you a lot for your instructions.

The decision whether a run needs to be repeated is based on a relatively complex algorithm and I use an external dll for the calculations.

Is it possible to use custom parameter scripting to start an external program that performs the mentioned calculations and returns a flag (e.g. "continue" or "repeat run")? If this option would work I could probably write my own "automation interface"?

Hi Slaven,

I understand you want to avoid having to buy the automation license.

A custom parameter script is able to call an external DLL.

However what you need is a "trick" to let the continue/repeat run decission take its action. There is only one way that I know (other than the automation interface) and that is what I tried to explain by using the system suitability functionality in a sequence.

1. Your DLL will tell the customer parameter to continue or to repeat. Let's say that continue=1 and repeat=0 as a return value of the custom parameter.
2. In the System Suitability conditions of the method it is specified that when your custom paramter <1 that the system suitability fails.
3. In the sequence you specify one or more system suitbalilty runs. In the action field of each run you specify that when system suitability fails the entry is re-run until it succeeds.

There is a substantial difference between a custom parameter (even if it links to an external DLL) and the Automation Interface. Using the Automation Interface you are in control of everything that goes on and you can orchestrate the exact flow of events in your application. In a custom paramter you can only answer if asked (i.e. you are a slave, EZChrom is the master). Sometimes this is good enough, but not allways.

JW
Applied Instruments
http://www.applied-instruments.com

Hi JW,

I understand you want to avoid having to buy the automation license.

I try to find the "best" way to solve my task. It seems that the automation toolbox gives me much more control over EZChrom.
But, can you confirm that I could reduce complexity and work by buying the automation license?

Slaven,

It would be helpful when you would describe in much more detail what your application is. Is it lab based? Is it more process based? Does it run in a compliant environment? Does the user intimately work with the CDS or is the main User Interface elsewhere?

Below is when to use the AI:

- For autonomous systems where no user interaction with the nitty gritty details of a EZChrom is needed, the focus of the user is in another application, not in EZChrom.
- For systems that classify as a 'robotic system', e.g. a sample preprocessing or complex measurement system that will be controlled by a complex software application, where the EZChrom analysis provides chromatographic feedback as to what has happened in the robotic system.
- For systems that have a monitoring or a database link for trend analysis and so on and that mostly will be linked to other system for process control or data monitoring.

If the above more or less describes your application then I would go for the automation system, otherwise try the other mechanism I proposed using System Suitability/Custom Parameter.

JW
Applied Instruments
http://www.applied-instruments.com[/url]

Hello JW,

we are going to install a multiposition valve to our GC. Our aim is to get multiple measurement results of diverse probes by "one click". Each measurement consists of several runs. I check the results within an external software and eventually repeat the measurement or - if the tests are ok - generate a report and start measuring the next probe.

As I now understand, for this kind of application - unattended measurements where EZChrom runs are to be controlled by an external program - the use of the AI is mandatory.

I appreciate your input. It will help us to make some design decisions for the (control+analyze)software that we are about to develop.

Hi Slaven,

I have been involved in this stuff for 10+ Years. We develop CUI (Custom User Interfaces) for EZChrom all the time. As said: there are many applications. This robotic device from Mettler Toledo (albeit HPLC) uses the Automation Interface too (developed by MT).

http://se.mt.com/mt_ext_files/Editorial ... 1250_e.pdf

You can control the multi position valve from your external application (most flexible) or you can use the VICI Valve Control capabilty of EZChrom.

I just finished a project earlier this year for a large Gas Manufacturer and did the valve control through EZChrom. In hinsight it would have been better to let the CUI control the valve because in EZCHrom the valve can only move to a next position after the run has been started! In my project this was a problem because we wanted to check column flow before the run was initiated on a HP6890.

Good luck with your project!

JW
Applied Instruments
http://www.applied-instruments.com

Hi JW,

I just finished a project earlier this year for a large Gas Manufacturer and did the valve control through EZChrom.

How did you connect the Valco Valve to your computer? Did you use the optional serial port of the multiposition actuator?

I'm just testing an USB 24-bit digital IO-Box from National Instruments for this purpose. I think that synchronization would be easier by connecting a flush valve and the multiposition valve (via BCD-connectors) to this NI-Box.

However, what development environment do you prefer for this kind of applications? I took a look at the API documentation of the Automation Interface. It's completely in VB. Though I personally prefer VB (.Net) we consider to use LabView for this issue because of the focus on instrument controlling and data acquisition.

Hi Slaven,

I used the RS232 connection to the VICI because that is what the EZChrom VICI drivers supports. However I would allways choose the RS232 since you have positive acknowlegde of the position of the valve. Only exception: Ex-Proof environments where pneumatic driven valves are the better choice. The VICI RS232 protocol is pretty straightforward and documented.

For CUI's I use VB6 SP6 because it is supported by the vendor. If you use something else and you need to log a support call you will be nowhere if you are using something else as the supplier is using.

I know about one company in Norway directly interfacing LabView to the Automation Interface so technically certainly possible.

JW

Hello JW,

this is my first project that handles gas measurements. Thus I trust a developer with 10+ Years of experience in this domain:-)

I've been envolved relativleey late in this project. The hardware is already there (the multiposition actuator without the RS-232 port...). Though it should not be a problem to change the current actuator I wonder why the default interface of the actuator is a 26 pin dual in-line connector! I assumed that by connecting the default 26-pin connector with the NI IO-Box I would have full control of the valve including a positive acknoledge of the position of the valve.