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RS485 instruction reply timeout is: the maximum time interval between the start of
sending this instruction and the receipt of the reply by the serial port server. The
filling time should be greater than the actual maximum time interval. If the timeout
is determined, the next instruction is sent.
Figure 38 RS485 conflict free time
RS485 bus collision time: indicates how many milliseconds the serial server waits
to send the second instruction after receiving the reply of the first instruction. This
parameter actually defines the speed of instruction rotation. This value is
recommended above 20ms. The "maximum wait time is 3 seconds" parameter
does not need to be modified.
When the user use ZLVircom to select "Modbus TCP to RTU" as the transfer
protocol, ZLVricom will automatically select the above two enabled boxes (unless
the user manually enters the advanced option to remove), and the above two
times will be automatically configured according to baud rate. However, if the
user's Modus instruction is relatively long or the conversion protocol is "none",
these two parameters need to be manually configured.
The following is the recommended setting values of the above parameters:
1) Figure 30 shows the "RS485 bus anti-collision time", which can be set as
twice of the "packet interval" in the lower right corner of the parameter
configuration interface, but the minimum value should not be less than 20.
2) Figure 29 shows "RS485 instruction reply timeout time", which is generally
determined according to the length of the reply instruction. If the sending
instruction is N bytes and the reply is M bytes, the recommended value is:
"packet interval" * (N+M+5) +100.
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