FMD-88-10 PLC

[chai_thing05]

Hi,

We used 32 nos of FMD-88-10 PLC and having a problem with lost communication/signal from plc.
tried to use "ping" command to check the connectivity and realized that there are many drop packet from PLC end.

Please advise.

[support]

What kind of communications ?

1) is it PLC to PLC (peer to peer)? Or
2) is it from PC to the PLC?
3) is it from PLC to the PC?
4) What communication protocol is being used (Hostlink command, Modbus/TCP, HTTP or FTP?)

Is the PLC at the same time also communicating with other devices using serial protocol? Are these serial link healthy (i.e. PLC is not wasting a lot of time waiting for response from non-existence slave)?

[chai_thing05]

Hi,

What kind of communications ? - TCP/IP

The ping command was executed by/from PC to the PLC.

4) What communication protocol is being used (Hostlink command, Modbus/TCP, HTTP or FTP?) -  RemoteFS

Is the PLC at the same time also communicating with other devices using serial protocol? - No.
Are these serial link healthy (i.e. PLC is not wasting a lot of time waiting for response from non-existence slave)? - Yes

[chai_thing05]

basically, my plc is pretty straight forward and simple as below.

1. press button cable connected to PLC-Input Terminal and LED light cable connected to PLC-Output terminal (located in Room A)
2. Assigned an IP address and PLC ID , PLC connected to network switch
3. When user pressed a button and LED light is ON at Room A, PLC will RemoteFS a message via IP address to Room B's user.

added to this, the transmission problems such as lost data packets is happen in intermittently ..

[support]

RemoteFS is ONLY for communicating with TLServer to perform special functions such as writing a file to the PC or sending out an email on its behalf. It is not for PLC to PLC communications.

What is the Room B user using to receive the message from PLC in Room A? Is it text messages, emails or is it another PLC?

In your first post said that you have 32 FMD88-10 PLCs connected to the network. May I know are these PLC talking to each other or all of them try to talk to another PLC?

Please explain a bit more clearly of your setup in order for us to understand what is the issue you face.

Are you able to use i-TRiLOGI to perform online monitoring on these PLCs? How is the connection quality? Do you often face communication errors when you perform online monitoring? If so then it is likely your networking equipment has some issues.

[chai_thing05]

RemoteFS is ONLY for communicating with TLServer to perform special functions such as writing a file to the PC or sending out an email on its behalf. It is not for PLC to PLC communications.
>> Yes, we used RemoteFS to writing a file (e.g Input/Output triggered) and send back to PC. TLServer is always turn on.


What is the Room B user using to receive the message from PLC in Room A? Is it text messages, emails or is it another PLC?
>> text file (.txt) and less than 1KB.

In your first post said that you have 32 FMD88-10 PLCs connected to the network. May I know are these PLC talking to each other or all of them try to talk to another PLC?
>> 32x FMD88-10 are standalone with one static IP and One workstation act as a Monitoring Signal from 32nos of PLC.

Please explain a bit more clearly of your setup in order for us to understand what is the issue you face.
>> 32 x PLC + one workstation connected to network switch, hence all devices are in same network.
>> for example, sometime user mentioned when they press a input button and didn't received any .txt from plc to notify them via workstation.
>> when encounter this problem, we did a ping test to ensure the network connectivity. unfortunately, there is many drop packet from PC ping to PLC.
>> 2nd, user just do a power cycle for the PLC , and do a same ping test again. the drop packet is gone.
>> after few days/weeks, same problem occurred again.

Are you able to use i-TRiLOGI to perform online monitoring on these PLCs?
>> YES

How is the connection quality? Do you often face communication errors when you perform online monitoring? If so then it is likely your networking equipment has some issues.
>>  we have other devices connected to this network switch , but the ping result is healthy also.

[support]

When the PLC is not responding to PING, are you still able to go online monitoring with the PLC via Ethernet to IP address of the PLC that is not responding to PING?  

Did you try to use another PC on the same LAN to ping the PLC?

When you use REMOTEFS to write to the TLServer, does your code check for the "<OK>" a response from TLServer (refer to this document C:/TRiLOGI/TL6/public/Help/fileservice.htm) - that way your program will know if the write to the TLServer is successful and it can do a retry. If failure persists after several retry it can issue a warning to the operator (e.g. turn on a warning light). The PLC can also be programmed to perform an orderly reboot of itself by saving critical data to FRAM and restart the PLC and reload the saved data from the FRAM. It can therefore complete the task after reboot.

[support]

We have sent your technical inquiry to the distributor that you have purchased the device from to support you directly. Please contact the distributor regarding your tech issue.