RC Systems ST-72, Инструкция по эксплуатации

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ST-72 User's Manual
Document: UM-1007 Revision Level A
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technicians time to trouble shoot and fix the problem. If the problem is not going to be
fixed, the warning message can be cleared permanently by disabling the redundant
port. If the user chooses to test the port and it passes, a success message will appear
and the error message will be cleared.
Before a Primary port switches to its redundant port, a scan must fail 3 times. All
channels setup to use the primary port are polled. At the end of the scan, if an error has
occurred on any channel, the error count is incremented. After 3 scans fail, the
redundant port takes over communication. If the redundant port also fails 3 times,
communication is switched back to the primary port. When both ports fail, the ST-72
will continuously switch between primary and redundant port.
Individual channels do not enter COMM ERROR mode unless both primary and
redundant port failures occur.
Manual test can be performed on the redundant or primary port by going into the
redundant port’s com setting menu and selecting
TEST REDUNDANT PORT or
TEST PRIMARY PORT.
While in this menu the ST-72 also gives the active port on
the screen.
2.5.1.1.5 Disabled
Select Disable to turn the port off if not needed.
2.5.1.2 BAUDRATE
This setting allows user to set the data rate of the communication port. The options
include
9600, 19200, 38400, 57600,
and
115200
.
2.5.1.3 PARITY
A PARITY bit is a bit that is added to ensure that the number of bits with the
value one in a set of bits is even or odd. Parity bits are used as the simplest form of error
detecting code. The default is
None .
2.5.1.4 TIMEOUT
The Master TIMEOUT menu item affects the ST-72’s master Modbus ports.
TIMEOUT is the length of time in milliseconds the controller waits before a Modbus
request fails. Three consecutive failed requests must occur before a communication
error is indicated. This item is useful for optimizing throughput to the ST-72 from other
slave RTUs.
2.5.1.5 POLL DELAY
The time in milliseconds the unit will delay between Modbus master requests.
2.5.1.6 SYMPATHY ENABLED
The sympathy feature allows multiple ST-90 Quad controllers, communicating on the
same communication port, to go into an alarm condition simultaneously when any one