ABB FENA-01, Protocol Manual

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Drive configuration
18
14-19 Reserved
These parameters are unused by the FENA-01 when configured
for Modbus/TCP.
20 MODBUS/TCP TIMEOUT
The Modbus protocol does not specify a timeout mechanism for
the application layer. A timeout mechanism may be desired when
controlling a drive, so a method is provided for this purpose.
If the parameter value is zero, then this feature is disabled.
If the parameter value is non-zero, then the timeout is
(Modbus/TCP Timeout Value) * 100 milliseconds.
For example, a Modbus/TCP timeout value of 22 would result in a
timeout of
22 * 100 milliseconds = 2.2 seconds
In the event of a Modbus/TCP timeout, the FENA-01 will signal the
drive that communication with the client has been lost. The drive
configuration will determine how it will respond. For example, if the
Modbus/TCP timeout is configured for 250 ms and the drive is
configured to fault on a communication failure with a delay of
500ms, then the drive will fault 750ms after communications is
lost.
21 TIMEOUT MODE
Selects which Modbus/TCP register accesses reset the timeout
counter.
0 = NONE: The Modbus/TCP timeout feature is disabled.
1 = ANY MESSAGE: The timeout counter is reset when any
Modbus register of the drive is accessed.
2 = CONTROL WRITE: The timeout counter is reset when the
drive receives either a new control word or new reference value
(REF1 or REF2) from the Modbus/TCP master.