Opc ua or Rest api

[ravig]

Hi All,

What is the best way to interface shopfloor connectivity to business application like MES. Our shopfloor is controlled by PLCs and some tester PCs.
Is Rest api or OPC ua fits better and why

Thank you.

 

[the_msp]

Generally, the PLCs sit at layer 2 (layer 1 being physical devices like motors, valves, etc), and MES is layer 4. Layer 3 is SCADA. Ignition SCADA for one can bridge between MES/ERP/SAP and has REST, SOAP and OPC UA built in.

 

[Old Man]

Couple of information bits. Opc-Ua would be great if all device are connected within a local network.

Rest-Api becomes useful if communication is done across the "Internet".

Now with that in mind most Plc's can communication with Opc-Ua protocol, and not so much with Rest-Api so some type of gateway may need to be used. There may be other limits set by the Rest-Api service, I use Rest-Api for collection different types of data and all of them limit the speed at which I can make the request.

Just some more information for you to consider.

 

[mk42]

Hi All,

What is the best way to interface shopfloor connectivity to business application like MES. Our shopfloor is controlled by PLCs and some tester PCs.
Is Rest api or OPC ua fits better and why

Thank you.

What protocols do the MES system support? What do the PLC's support?


I know recent Siemens PLCs have OPC UA built in, and I think they have a REST API, or something similar.

 

[ravig]

Siemens with OPC UA.. we have intermediate kind of light mes application which collect shopfloor data and stores.. above that we have MES system.. i am confused whether MES should connect shopfloor with OPC for better visibility and control or connect with intermediate application with rest api interface.. intermediate app. Connects shopfloor layer with their own interface...

 

[ravig]

Thank you all for your answers... it really helps... pls share your experience or solution for my query...