Chapter 5 AC drive Operating Instructions
ACH200 Series High Voltage Variable Frequency Speed Control System Operating Manual
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selected through the display.
2) Remote DCS control of AC drive
When the switchgear is controlled remotely, the control command is controlled by the remote
terminal, which mainly controls the start/stop of the AC drive. And the frequency setting mode is
selected by the display.
5.4 Operation Mode of AC drive Speed Control System
1) Open-loop operation
After the system is ready, if there is a start command, the high-voltage AC drive speed control
system will start from the shutdown state according to the acceleration time provided by the system,
and finally run according to the frequency set by the user. That is, the frequency of AC drive
operation is only controlled by the personnel unilaterally.
2) Closed-loop operation
If closed-loop operation mode is selected in the parameter setting, the high-voltage AC drive
speed control system will operate in closed-loop mode after starting. In the closed-loop mode, the
user can set the desired value of the controlled quantity (pressure, etc.), and the high-voltage
frequency conversion speed control system will automatically adjust the motor speed according to
the actual value of the controlled quantity and the PID parameters set by the system, so that the
actual value of the controlled quantity automatically follows the desired value.
3) Normal shutdown
During the operation of the variable frequency drive, as long as the external shutdown command is
issued, the high voltage variable frequency drive speed control system can be shut down according
to the shutdown mode set by the parameters.
4) Emergency shutdown
In any case, the "Emergency Stop" button on the local panel is valid. When the system receives
the emergency stop command or a fault occurs, the pulse will be blocked immediately, the system
will stop freely and the vacuum contactor of the system switch cabinet will be disconnected at the
same time, only if there is no emergency stop command, the contactor inside the system switch
cabinet can be closed and the AC drive can start.
If an emergency stop is needed to disconnect the user's high voltage, set the multi-function
output terminal in the touch screen to "superior switch disconnect request".