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"Response Timeout" and "Receive Data too long" occurred .


This section explains the detail of "Response Timeout" and "Receive Data too long" errors.

Response Timeout


This error occurs when a timeout is detected after the elapse of a certain period of time without any response from the PLC.

<Main causes>

・PLC power failure / Cable break

・High network load

・Received packets are cleared by Windows ARP processing

・High CPU load on PC

・The timeout setting value is smaller than the PLC response time.


Check if there are any problems with physical factors such as a broken communication cable.

If there is no physical problem with the network, try "Extend Timeout" or "Retry" in the OPC server settings.

These settings can be configured from the port properties of the OPC server.

If the high network load is the cause, please distribute the network to reduce the load.

Receive Data too long


This error occurs when the size of message the OPC server received is not matched the expected size.

<Main causes>

・Network collisions

*It often be caused by the network collision when Response Timeout occurs.


The "Receive Data too long" may occur with "Response Timeout" at the same time.

In that case, it often be solved by eliminating the "Response Timeout".