Issue we are facing with WIZ100SR

It is regarding the issue we are facing with WIZ100SR. It is as follow.

Many Times we have observed communication break between our PC (server) and controller unit in Running conditions ( Attached system block diagram for reference.). It will not recovered until we switch on – off the power of the WIZ100SR unit. It's occurring frequency is about 5 out of 100 unit and not restricted to any specific unit. 

On further investigation we found that, many times communication is re-established when WIZ100SR is reset or Micro controller is reset. And also sometimes both resting is not working then we have to do complete power on-off.

We have taken care of micro controller reset using watch dog timer. It is working satisfactory.

As for the WIZ100SR We have doubt that may be it goes into Hang or similar like state and recovering only after reset.
In our current PCB, don’t have facility to reset WIZ100SR using controller (IO pins restrictions). So we are trying to understand situation so that we can avoid it. With regards to this we have further quires.

  1. Earlier we were using EG-SR-7100 with satisfactory results. After it is obsoleted, we changed to WIZ100SR without any modification in hardware or firmware. So are there any modifications which we have to consider regarding migration-to WIZ100SR?

  2. Attaching screen shot for WIZ100SR configuration tool with our set values. Are there any parameter values which can cause above issues?
    Also attached RJ45 & WIZ100SR connection diagram. Hope this much of information is sufficient for our analysis. If anything require, please let us know.
    Thank You.
    WIZNET Query.rar (346 KB)

Hello, rohitlokhande.

Looking at your attachment, the Module is acting as a Client and the PC is acting as a Server.
Here is the question.
You set the Inactivity Time to 5000 sec. If so, is a module maintaining a connection for 5000 seconds?

Or are the ports connected to each module set differently?

We need more information. In particular, you need information about what data (including size) is being exchanged at what time intervals.

If possible, it is helpful to attach a screenshot of the Configuration Tool when using the EG-SR-W7100.

In addition, when there is a problem, can not search in ConfigTool at all?


Hello kei ,

Yes, Ports are set differently.

Data exchanged is similar to the MODBUS protocol. PC sends query on every 1 sec to a particular unit (client) & Controller 

respond to it immediately. Size is 39 bytes.

Also it is observed that, ConfigTool not able to search the particular unit.
Attached IIM 7100 tool screen shot.


There seems to be no problem in setting the module.

However, your firmware of WIZ100SR is an old version(4.6).
The latest version of WIZ100SR firmware is 5.13.
Please update the firmware of WIZ100SR to the latest version and test again.


Best regard,

We have done firmware changes as above said. It is under observation .

Another query that we have, WIZNET100SR become hot during run time. Specially U3 IC on it. So we monitored temperature of U3 IC. It is around 50°C at ambient temperature of 32°C. We measured it in lab. Where our panel are installed, may have temperature well above 40°C. so can it lead to above said issues ?

The U3 IC is a W5100 chip. Please check the following link for temperature information.

Therefore, operation at 50 ° C is not a problem.

However, the temperature at which the panel is installed can be further increased by using WIZ100SR.
It will not rise above 50°C, but you should consider this.