Hi~~^^

I just ask about Modbus TCP Protocol. We're going little big project. Customer want to connect and receive data from 2500pcs device through MODBUS TCP Protocol without OPC server at the same time.

I afraid disconnect of MODBUS TCP.

Because of MODBUS TCP is Ethernet Protocol.
As I know it's different Ethernet TCP/IP Protocol.
Customer should receive data throgh MODBUS TCP in real time.
Server PC should receive within 200ms from 2500pcs device at the same time.

In general, data size of one device is about 100 bytes.

Please advice to us how to connect 2500pcs device through MODBUS TCP safely.

Thank you

 

> Customer should receive data through MODBUS TCP in real time.
> Server PC should receive within 200ms from 2500pcs device at the same time.

This is not really a Modbus question - talk to a 'business server' company. 2500 devices talking 5 times per second is 12,500 packets per second. I assume some commercial 'web servers' with powerful, highly intelligent network cards can handle this - for example, for $1200 you can buy a 4-port Ethernet 'server' card designed to optimize network traffic.

Someone like Wonderware trying to focus on business/SAP/ERP level data polling might have better answers for you on massive devcie counts.

If you don't want to get into business-class servers, you can probably use multiple lower-cost servers (for example 5 servers, each handling 500 devices) and have these servers concentrate and summarize data for a 6th SCADA machine which only talks to 5 devices (the other servers).

 

Hello,

I agree with Lynn August Linse.

You can use traditional SAP/ERP data-logger kind of solution.
Or, You need to have a very good client-server application that can handle such 15000 packets/second to talk to your 2500 devices.

You can use the solution provide by www.parijat.com.
we are developing the different protocols in .NET platform to communicate multiple instruments at the same moment.

We have the solutions that can talk on MODBUS TCP protocol for multiple devices using our device driver scanner application.

Thank You,
Dixit Solanki
www.parijat.com

 

Just a quick adder on wide-area latencies.

You did not say if all 2500 devices are one a single site, but if they are remote via DSL/wired broadband, then you can easily see 70-150msec latencies end-to-end, so even completing 1 Modbus/TCP transaction 100% of the time in 250 msec is doubtful.

If cellular is involved (I doubt you can find a cell plan allowing that much traffic!), but cellular easily has 500 to 2500 msec latency end-to-end (not device to tower, but device to host ... the cellular carriers like to tout 3G low-latency by quoting meaningless internal times, what I equate to jacking the powered wheels of a car up to see how fast they turn, and calling that 'max car speed')

 

Hello,

I have discussed about your project to my Superior Mr. Rakesh Verma.
He told me that, our device driver can talked to 10000 devices at an instance.

We can provide you a proof of concept for the project.

For more detail you can talk to Mr. Rakesh directly on 001-713-935-0900.

Thank You,
Dixit Solanki
www.parijat.com