I need to take devices off-line for maintenance on my RS232/RS485 network and I am using a CEV30010 or CEV30020 Modbus to Ethernet bridge. I notice that if I take a serial device off-line, it affects other devices that have Ethernet to Modbus communications through the bridge. What can I do?

Decrease your Modbus Message Time Out value. As only 1 outstanding Modbus message is allowed on the serial side of the network, the default timer of 5,000ms (5 seconds), will have to expire before the subsequent message in the queue will be sent.