PLC choice question 1

[xyzz]

Using currently Mitsubishi FX1N/FX2N, I need for some projects a faster PLC (meaning shorter scan time).
The ideal choice must meat at least all of the following:
- Be a single-unit enclosed PLC with 24VDC power and transistor outputs.
- Be expandable.
- High-speed inputs on the main unit capable to support at least 2 quadrature encoders.
- At least 2 high-speed outputs on the main unit.
- On-line editing feature is a must.
- Typical scan time <=2ms per 1000 program steps.

Any suggestions will be greatly appreciated.
Please do not suggest PLC missing any of the above.

Thank you.

 

[JesperMP]

Your requirement that it must be a single-unit PLC certainly narrows down the field of possible candidates.

The Siemens S7-314C-2DP (or S7-314C-2PtP) seems to meet your specifications.
It has 4 hi speed counter inputs. I believe they can be setup to 2 quadrature inputs (but do check it yourself).
It has 4 outputs with PWM functionality.

 

[OldPfart]

If you want something really fast, have a look at the Omron CJ1. The high end processors are about the fastest thing around right now. Awesome instruction set.

This is a rack type PLC with no rack. Just clip it together on a DIN rail.

You would have to buy cards for the unit but it will give you everything you need. There are about 10 different CPUs, all with different capabilities. Some of them include high speed inputs etc. 24VDC power supplies are available. I use them all the time on generator jobs.