BECKWITH ELECTRIC M-6280A, Инструкция

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Configuration – 4
4–147
Remote Control Mode Settings
The control is in Remote Control Mode (Figures 4-60
through 4-64) when an active DNP communication
channel exists between the control and a client
device. If the SCADA HeartBeat feature is enabled,
communication must occur in such a way as to
refresh the SCADA HeartBeat timer before the
timer expires, otherwise the control will revert to
Auto Control Mode. In order to execute a Close or
Open command from the client device when the
SCADA HeartBeat feature is disabled, the client
device must first send a "Remote" command to the
control in order to block automatic operation. When
the Remote command is received the control will
then operate in the Remote Control Mode.
In the normal Remote Control Mode when the
SCADA HeartBeat feature is enabled, the control
will receive an Open or a Close command from a
client application.
When the control receives an Open command from
the client, the control, will evaluate the following
inequalities based on if Remote Control Limits or
the Control Mode Limits are enabled before making
a decision whether to allow or inhibit the Open
command.
Remote Control Limits enabled:
Vm -
∆
V < Undervoltage Limit, then Inhibit
Open Command.
where Vm is the instantaneous measured
load voltage.
Remote Control Limits Disabled and Control Mode
Limits Enabled:
Vm -
∆
V < Minimum voltage Limit, then
Inhibit Open Command.
where Vm is the instantaneous measured
load voltage.
When the control receives an Close command from
the client, the control, will evaluate the following
inequalities based on if Remote Control Limits or
the Control Mode Limits are enabled before making
a decision whether to allow or inhibit the Close
command.
Remote Control Limits enabled:
Vm +
∆
V > Overvoltage Limit, then Inhibit
Close Command.
where Vm is the instantaneous measured
load voltage.
Remote Control Limits Disabled and Control Mode
Limits Enabled:
Vm +
∆
V > Maximum voltage Limit, then
Inhibit Close Command.
where Vm is the instantaneous measured
load voltage.
In the Remote Control Mode there exists a situation
where the control will automatically make an
operation without receiving a command from the
client device. This situation arises when the load
voltage goes outside the remote limits.
Now the Overvoltage Limit setting becomes the
upper threshold limit above which the control will
initiate an Open operation by loading an Open timer
with the Voltage Limit Timer Delay specified by the
user. When the Open timer expires, the control will
determine whether the Open operation will cause
the load voltage to drop below the Undervoltage
Limit, if so the control will inhibit the Open operation,
otherwise the Open operation will take place. The
following inequalities are used to determine if the
Open operation is inhibited.
Remote Control Limits enabled:
Vm -
∆
V < Undervoltage Limit, then Inhibit
Open Command.
where Vm is the instantaneous measured
load voltage.
Remote Control Limits Disabled and Control Mode
Limits Enabled:
Vm -
∆
V < Minimum voltage Limit, then
Inhibit Open Command.
where Vm is the instantaneous measured
load voltage.