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Hi,
I am interested where i can find robust Modbus slave devices simulator. It needs to be able to handle as much as possible Modbus requests for analog values, to afford access up to 10000 registers per second.

That tool will be used for testing Modbus SCADA master in extreme critical conditions.

Does on the market exists such software tools, or tools that have approximately similar performance?

Thanks in advance.

If this is Modbus/TCP (and not one of the serial versions), have a look at http://sourceforge.net/projects/mblogic/

The MBAsyncServer package can be used as a server for load testing masters (clients). The MBPoll package can be used as a client (master) for load testing servers.

MBPoll has options intended for load testing, and can be used to report on the actual transfer rate. MBAsyncServer will accept the data but does not provide reports, so you will have to measure the achieved rate some other way (adding an option to do this though shouldn't be hard, if you can tell me what you need).

How much speed you will get will depend on how fast your computer is and whether you are communicating with another PC or to the same PC over localhost. However, if I use MBPoll to poll MBAsyncServer with both running on the same (low end) PC, they will do more than 1,000,000 registers per second. Your requirement for 10,000 registers per second then shouldn't be a problem.

However, the actual rate you do get will also depend on the size of the message. The above mentioned (1,000,000 registers per second) rate was achieved by reading a large number of registers at once. The overhead in handling messages means that a small message takes almost as much work to deal with as a large message. This means that large messages (e.g. 100 registers) are handled more efficiently than small messages if you are measuring them on a per-register basis. This in turn means that you should be thinking as much about messages per second as you are about registers per second.

Hi,
I have one question about MBPoll master.

What is exactly measured elapsed time: is it time required only for master to send all requests to slave, or total time required for sending all requests to slave and receiving all responses?

Thanks

Have a look at Automated Solutions Modbus Slave product.

http://automatedsolutions.com/products/modbusslave.asp

Assuming your talking about Modbus/TCP, reading 10,000 registers take 415mS to 833 mS depending on network conditions.

Comes with ready-to-run example app and 30 day trial.

Try controltoolbox.com. NetPro-ModServLite is a product that allows you to simulate up to 65535 modbus TCP slave RTUs in one application. It runs full features for 30 minutes for free.