ABB FSCA-01 User Manual page 36

36 Start-up
No. Name/Value
05 Parity
0 = 8 None 1
1 = 8 None 2
2 = 8 Even 1
3 = 8 Odd 1
06 Modbus timeout
0...65535
07 Timeout mode
0 = None
1 = Any message
2 = Ctrl write
Description
Defines the use of parity and stop bit(s) and
the data length. The same settings must be
used in all on-line stations.
No parity bit, one stop bit, 8 data bits
No parity bit, two stop bits, 8 data bits
Even parity indication bit, one stop bit,
8 data bits
Odd parity indication bit, one stop bit,
8 data bits
The Modbus/RTU protocol does not specify
a timeout mechanism for the application
layer. ABB Drives and the FSCA-01
module provide a Modbus timeout method
as it may be desired for drive control.
The timeout is:
(MODBUS TIMEOUT value) * 100 milliseconds
For example, a MODBUS TIMEOUT value
of 22 would result in a timeout of:
22 * 100 milliseconds = 2.2 seconds
When a Modbus timeout occurs, the
adapter module signals the drive that
communication with the master has been
lost. The drive configuration determines
how it responds.
Example: If you configure the MODBUS
TIMEOUT as 250 ms and the drive is
configured to fault on a communication
failure with a delay of 500 ms, then the
drive faults 750 ms after the
communication is lost.
Modbus timeout value
Selects which Modbus register accesses
reset the timeout counter.
Modbus timeout feature is disabled.
Timeout counter is reset when any Modbus
register of the drive is accessed.
Timeout counter is reset when the drive
receives either a new Control word or new
reference value (REF1 or REF2) from the
Modbus master.
Default
0 = 8 None 1
0
0 = None