Cannot get a query from USB Tekpower TP3005P power supply

[MLAB]

Hi everyone,

I am having a problem with getting a simple *IDN? query from my usb connected DC power supply through VISA test panel.  The device is shown in NI MAX as ASRL5::INSTR"COM5" and device status is working properly I get timeout error when trying to get a query.  FYI, the interface works with their own data logging software and in their user manual they have example SCPI commands. 

Thank you in advance for the help!

[mkossmann]

Sice the the device shows up as ASLR device , it seems that the device uses a serial connection over an USB to Serial converter. Did you allready play with the termination character settings for that serial connection ?

[MLAB]

Hi Mkossmann,

Thanks for the reply.  Well in their data sheet they have \n at the end of each command, so I tried *IDN?\n and I enabled the termination character (\n) in VISA Test Panel and it did not help.  Any thing else I can try? 

[crossrulz]

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@MLAB wrote:

Thanks for the reply.  Well in their data sheet they have \n at the end of each command, so I tried *IDN?\n and I enabled the termination character (\n) in VISA Test Panel and it did not help.  Any thing else I can try? 

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In the VISA Test Panel, you should only write "*IDN?".  The termination character should be added automatically for you.

Have you tried a terminal program like Putty yet.

[MLAB]

Hi Crossrulz, 

Thank you for the response.  Yeah, that's what I meant, it automatically added the \n.  Also, I've tried to do serial connection through PuTTY, it opens a session but nothing happens when you press Enter. But, this is the case for my other power supplies whose remote control actually work, so I'm not too worried about that.

Could it be because the power supply is cheap? but, how come the have examples of SCPI commands and that it works with their own software (which print the corresponding SCPI command to the screen)?

[Minions]

It all comes down to your serial connection settings.  If they are properly configured, you should be able to send:

*IDN?;

and get the proper response from the instrument.  A SCPI compliant instrument will interpret the ";" the same as a newline character.  If you are still having issues, could you attach your vi?

[crossrulz]

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@Minions wrote:

It all comes down to your serial connection settings.

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I do believe this is exactly the case here.  Go through the menu items on the oscilloscope and see if you can find the serial port settings (baud rate, parity, stop bits, data bits, etc).  Make sure they match the rest of your power supplies.

[MLAB]

Thanks again for the response.  I think the serial settings are correct and the match what is used by their own data logging software (look at the bottom of the attached picture).  I've given up on this cheap power supply...

[Minions]

Both pieces of software will not be able to control the instrument at the same time.  Are we certain that it is releasing control when that software terminates?  Also, that image does not address flow control settings.

[Luke.jar]

I know this thread is a bit old, but in case someone happens to be working on a similar project and finds this...

I have a TekPower TP3005P Power supply and have gotten to interface with it. You have to send it literal "\n". So, for the *IDN? command, the string you need to send is "*IDN?\n".