Communicating with ISO-TECH IPS-2010

[JBeebs]

So, I have an annoying issue with communicating with this power supply. 

I have an ISO-TCH IPS-2010 power supply and would like to be able to control it completely from LabVIEW. I've made a quick library (attached) and the VIs for writing voltage and current to the power supply work. I can send commands via VISA write to the COM port and the screen on the power supply shows the updates to the voltage and current. 

However, I don't seem to be able to get anything back from VISA read. For example, sending the command "V<cr>" should get the power supply to send the output voltage back. I use a Visa property node after writing this command and the bytes at the serial port property returns "0" and so any read function with a non-zero bytes to read will (and has) time(d) out. 

I should add that I am connecting using a usb to serial hub if that might be a cause.

So my question is: 

Are there any common traps I may have fallen into?

Has anyone else tried communicating with this device before and did it work?

Any ideas for ways to fix this?

Appreciate any help.

[Albert.Geven]

Hi

I did not yet look at your driver but will do this weekend.

But if you have an "end of message" character, use that instead of bytes at port.

In visa initialize set the endcharacter and set  enable end character True.

Then execute a visa read for say 255 characters and that function will stop on the first endcharacter or tries to read 255 characters. You eliminate a lot of critical timing that way. So in your case set the end char to decimal 13 (CR) and try.

[JBeebs]

Hi Albert,

Thanks for the fast reply 🙂

I've just checked how I set it up and I think it is now set up as you suggest but unfortunately it still does not work. Instead of getting a "successful" VISA read of zero bytes, it now returns a VISA read timeout error (-1073807339). I've attached the updated project so you can see what it looks like now.

JBeebs

[Albert.Geven]

Hi I looked into your previous code and saw that inside the init the system was initialized for an output character but not for input.

attached the new init and new  control panel

except for that one wire in the init (termchar to ASLR  end in) I only changed the layout to more compact and less wire bending.

I'm also not a fan of initialize to default values.

But I did not see a read function in the control program and only a limited set of the library was included in the project. No read functions.

[pepper2]

Hi,

im not sure exactly which pin (i think 4) but there is one pin from the DB9 that should go to a separate 12v ps. Check the manusl on the pin out section. This will supply the optos that isolates the psu from the exterior.

It s a bad design from this point of view.

[JBeebs]

Thanks for the help and sorry for my late reply!

I tried the changed VIs but no luck. I am still to try the 12V power supply on the pins - sort of hoped the computer would do this/can be told to do so otherwise there will be some interesting wiring to be done. Will try when I get the time. 

JBeebs