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DCS/PLC CPU models

DCS/PLC CPU models

DCS/PLC CPU models

I don't suppose anybody could tell me what model of processors are used in common industrial PLC/DCS controllers? I assume the majority are Intel based possibly Xeon for higher end controllers. I heard some old Siemens S7 CPU's use Mitsubishi chips.

I'm more concerned about DCS controllers since they handle a lot more network data. I just want to do a small study on industrial controller performance.


RE: DCS/PLC CPU models

I think what your asking is controller connection limit. Thats all in detailed user manual PDFs provided by the manufacturer of the dcs/plc or pac controller.

RE: DCS/PLC CPU models

I'm not asking for facts and figures and yes I have the controller spec sheets I'm talking about microprocessor models.


RE: DCS/PLC CPU models

I don't expect they use typical LGA socket type processors found in personal computers no but I know for certain they don't produce their own chips except maybe Honeywell but still I doubt. I suspect at least some of the processors are of the Pentium/Xeon x86/64 family. Smaller PLC CPU's possibly not, I would guess at Texas Instruments/Motorola RISC type models.

RE: DCS/PLC CPU models

I have been told that the SLC 5 series uses an Intel 186 processor to handle communications, math and timer operations. Boolean logic is solved with a custom chip.

RE: DCS/PLC CPU models

The biggest issue you have with the type of processor is the endian format of the data.

Allen Bradley = intel = little endian format
Siemens = motorala? = big endian format

Not sure what the other manufacturers use?


If your integrating the two processor above you need to be aware of it.

RE: DCS/PLC CPU models

I have been told the same as 'djs' about the SLC 5 series.
But I have never heard that Siemens use a Motorola processor.

Kind regards

RE: DCS/PLC CPU models

Honeywell's HC900 (a modular I/O rack PAC, process automation controller, not a PLC) CPU module uses the e300 32 Bit RISC based PowerPC Architecture, according to its spec sheet.

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