Rx Delay (ms)
Suppose the Rx Delay is set to 1000 ms (one second), it means the whole received data will be sent to the PC host after 1000 ms (one second) upon receiving the first data from the Modbus device.

Tx Delay (ms)
Suppose the Tx Delay is set to 1000 ms (one second), it means the whole received commands will be sent to the Modbus device after 1000 ms (one second) upon receiving the first command from the PC host.

Message Timeout (ms)
Suppose the timeout is set to 1000 ms (one second), it means a timeout signal will be sent to the PC host if the Modbus device does not respond within 1000 ms (one second) starting from sending the first data to the Modbus device.

Minimum time interval of queries (ms)
Suppose the Minimum time interval of queries (ms) is set to 3000 ms (3 seconds), which means that the fastest interval is 3000 ms (3 seconds) between the currently sent query and the next query sent to the Modbus device, regardless of the setting of the Rx Delay, Tx Delay and Message Timeout.