Edwards nEXT200200, Инструкция по эксплуатации

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6.4 Mixed parallel and serial operation
In mixed parallel and serial operation, the pump can receive commands from serial and
parallel interfaces. Refer to Figure: Serial and parallel control flowchart on page 69 to
understand how the commands controls the pump. The pump will power up with 'None
in Control'. From this state a parallel start signal or a serial start command can receive,
which can move the pump to parallel control mode or serial control mode. Serial start
commands can receive only if the serial enable line is active.
The state of the serial enable line can be switched between active and inactive while in
mixed parallel and serial operation. The primary function of the serial enable line is to
enable the serial link. It has no direct effect on the control mode. The pump will receive
and respond to serial commands whenever the serial enable line is active. The pump will
not receive or respond to serial commands when the serial enable line is inactive.
Availability of the parallel standby and fail signals depends on the state of the serial
enable line and the position of the RS485/RS232 switch as given in Table: Serial enable
matrix on page 68 .
Table 20
Serial enable matrix
RS485/
RS232
switch
Serial enable
Active Inactive
RS232
Standby and fail lines are used for
RS232 data.
Standby and fail lines are used for
parallel Standby control and fail
indication.
Parallel standby control and fail
indication are disabled.
Serial communications are disabled.
RS485
Standby and fail lines are used for
RS485 data.
Standby and fail lines are in (RS485)
high impedance state.*
Parallel standby control and fail
indication are disabled.
Serial communications are disabled.
* The pump target speed will change between run speed and standby speed in response
to data driven onto the RS485 bus by other devices connected to the bus. Do not activate
the parallel start line when the RS485/232 switch is in RS485 position and serial enable
line is inactive. Do not deactivate the serial enable line when the pump is in operation
after a start from the parallel start line and the RS485/232 switch is in the RS485
position.
In parallel control mode, the pump does not accept serial stop commands but will
accept all other serial commands. When serial enable is active, the pump will operate at
standby speed if the serial standby command is given. When Serial Enable is inactive and
the RS485/RS232 switch is in RS232 position, the pump will operate at standby speed
when the parallel standby line is active.
In serial control mode, the state of the parallel Start line will be ignored but the serial
enable line gives an interlock function as shown in Figure: Serial and parallel control
flowchart on page 69 . This interlock function only operates with serial start commands
and in serial control mode only. In serial control mode, the pump cannot be commanded
to standby speed by the standby line, instead a serial standby command must be used.
Page 68
B85200880_D - Operation