Desperate cause? device cleared for EVER

[anbere]

Hi, even tho I think I set everything correctly. My Lambda EMS II power supply with RSTL programming interface can't respond to simples GPIB commands.

In fact, all it does is sending me this perpetuate message : device cleared........ No matter the command. I have tried almost everything i could find on the net or in manuals.

If i keep harrassing it with some commands, the some strange thing happen, lets say I harras it with *IDN?, the it'll go

device cleared

device cleared

(bis)

IDN?ce cleared

IDN?IDN?leared

IDN?IDN?IDN?IDN?IDN?IDN?IDN?IDN?IDN?(forever)

sometimes it ponctuates with some other commands i sent like 5 minutes ago...like IDN?IDN?IDN?IDN?RSTIDN?IDN?IDN?RST(forever again)

Please what's gotten into it? Is it possessed? How can i exorcise that kind of demon?

ty

Antoine

[Brian F.]

Hi Antoine. 

Thanks for posting to the NI Discussion Forums. 

That seems to be some strange behavior that you are experiencing.  I have a few questions and suggestions so I can help you find out what is going on here. 

First, I am not terribly familiar with the instrument in question and searching our website and google didn't turn up much.  So, first, is the Lambda EMS II power supply SCPI compliant?  In other words, are you sure that commands such as *IDN? are valid commands to be sending to the instrument?  Also, is it expecting some sort of termination character signaling the end of your transmission?  Secondly, can you explain the RSTL programming interface that you are talking about?  Thirdly, what device are you using to communicate with the instrument?  Is it one of our GPIB's?  If so, which one? 

Also, if you use Measurement and Automation Explorer (MAX) which is a NI software program, you should be able to detect the instrument.  Are you able to see the instrument in MAX?

Let me know and I will be happy to provide you with whatever assistance I can. 

Have a great day!

Brian F
Applications Engineer
National Instruments

[anbere]

Thank you for responding.

The EMS series is there http://www.lambda-hp.com/product_html/emspower.htm, there's only one manual for all EMS device on the site, but i have compared the shipped manual exclusive to my device and the one on the net and they agree....My device, the EMS 2 is listed as EMS 10-500,....10V 500A 5000 W.

So basicly, if you buy that kind of source, you will have a controle panel at the front but no GPIB or any port. To communicate with the source using a pc, you gotta buy a RSTL, a little improvement that connects to the rear of the actual EMS device and allows one gpib port.

As for the termination caracter, i have not seen any information about this in any manual, but i have tried all the termination options a it didnt change anything. The manuals, however, specify that the EMS(RSTL) should respond to a *IDN? query, among others. The two manuals are at the upper left corner of the site i linked, the product manual (EMS), and the RSTL programming guide.

Finally, the ni instrument detection or something like that detects it, and where it should be showing the instrument brand and model, like it does with the keitley  or anything else, it shows "device cleared".

I'm using a national instrument cable, but im not at the lab right now so its hard to tell you wich one, i think it's GPIB-USB-HS. I'm also using HP GPIB splitter to communicate with the keithley at the same time, but the adress don't interfere.

thank you,

antoine

[Dennis_Knutson]

What is a 'HP GPIB splitter'? Normally, in order to talk to two different instruments, all you need is two separate cables. Have you tried removing this thing and connecting the power supply directly to the GPIB controller? I would also recomend trying it as the only instrument connected.

[anbere]

The GPIB slitter...worked fine in many applications, I dont know how to describe it with accuraccy, but it's oubvioulsy not artisanal and meant to be used that way.

Anyway, I tried with and without, and it didnt change much.

Thank you and please do not give up suggesting.

[Dennis_Knutson]

Have you talked to Lambda about this issue? I think there's a good chance that there is something wrong with it. Maybe there is a problem with the firware or the installation of this RTSL interface. If MAX is able to detect other instruments with no problems, that would say to me that there is nothing wrong with the GPIB controller or the NI driver. Just to be sure, can you try to detect the instrument on a system with a different GPIB controller?

[anbere]

I have tried with 2 different national instrument GPIB cables. I get the same device cleared message. Knowing this, the lambda source could be the problem.

However, i tried with a different lambda source, another of the EMS series. witch is different only by its specs. 33-150 instead of 10-500.

Both device seem locked in a device cleared state. Since both RSTL on these soure are factory installed, i doubt they made the same mistake twice, and the installation of the RSTL on the source matches the instructions of the RSTL manual. I set the forced local switch to off, back then i though it was the cause of the device not responding, but it's not. Also, i have checked for possible Lambda help, and the ressources i've found are small independant authorized reparator, and i doubt they would know about what seem a software problem.

When i reconnect my GPIB cable, the windows xp assistant keep installing the driver over and over. Is there like, an improvement of the driver that could fix the problem or is there only one driver?

[Dennis_Knutson]

Lets get some terms correct. A GPIB cable is one of these. An external controller is this. I think that when you mention plugging in different cables, you are talking about different external controllers. The latest version of NI-488 can be downloaded here.

[anbere]

k lol so when i said GPIB cable i meant controller and when I said gpib splitter i meant GPIB cable...sorry

[anbere]

hehehe, well, just for the records, all i had to do was including both \r and \n at the end of my commands...><

that's pretty dumb but if you don't know, you don't know...(line feed and carriage return)