SCPI programming / instrument automation

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1

Not sure where to post this. I’m developing test systems to automate production processes. My role is to automate the instrumentation. There’s various industry standard protocols for talking with them. Curious if anybody knows a community / forum with programmers whom deal in instrument automation?

Specifically right now I’m trying to create a windows GUI to utilize VISA / SCPI instrument interface. It would take readings from an instrument and check them against production spec to report pass / fail.

I DO NOT want to utilize LabView. Rather .NET or compiled MFC (C++). I’ve got Python working but want a GUI.

2

Anybody know how to connect a PLC to a generic interface like ethernet, or USB to talk to a 3rd party device such as a rack mount digital multi meter?

3

When it comes to connecting a Programmable Logic Controller (PLC) with a device, you simply use an Ethernet interface or even a Universal Series Bus (USB) interface and in order to do that you need to ensure that both the controller and the third party device, in this case, a rack-mounted digital multimeter would employ an identical kind of interface. Almost all PLCs provide Modbus TCP/IP, Ethernet/IP, or Profinet for communication over Ethernet interface. For USB interfaces, most PLCs need to have drivers or some other interface boards to connect the equipments of other manufactures. After checking the compatibility, set up the necessary parameters for the message exchange and merely choose the proper protocol regarding PLC setting, for instance, IP address for Ethernet or COM for USB. After it, you can set up the connected communication via PLC to transmit data to and from the multimeter, with different commands and data format the device type supports.

4

Thank you @Rabert seems the operative items are Modbus TCP/IP, Ethernet/IP, or Profinet. I’m 95% sure it’ll be over TCP/IP. I need to establish a socket connection, then send commands via ASCII scripts to instrument which replies with ASCII responses. Those responses then need cast into floating point numbers and compared against production specs…

Once comparison is made to production specs the routine will signal for actuators connected to PLC to either discard components are move them further along in the test process. Currently I believe there’s a PC in the loop to carry out the instrument automation, then talk to the PLC. I’m hoping to eliminate the PC but have no experience with PLCs.

Thanks for the help. I’m going to look into those protocols.

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