ABB ACH400 Series, Руководство пользователя

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Chapter 2 – Overview of ACH 400 with Electronic Bypass
2-6 ACH 400 with Electronic Bypass User’s Manual
Hand LED The Hand LED is illuminated green when the motor has been started
manually in the bypass mode.
Auto LED
The Auto LED is illuminated green when the Auto Start contact has been
selected as the means for starting and stopping the motor in the bypass mode.
Automatic LED
The Automatic LED is illuminated green when the Automatic Transfer to
Bypass feature has been selected.
Auto Key The Auto key selects the Auto Start contact as the means for starting and
stopping the motor in the bypass mode.
Reset Key The Reset key resets the bypass fault.
Drive Select Key
The Drive Select key selects the ACH 400 drive as the power source for the
motor.
Bypass Select Key The Bypass Select key selects the bypass as the power source for the motor.
Hand Key
The Hand key can be used to manually start the motor when the bypass has
been selected as the power source for the motor.
OFF Key
The OFF key can be used to manually stop the motor if the motor has been
running on bypass power.
Operating Modes
Drive mode
Under normal conditions the bypass is in the Drive mode. The ACH 400 drive
provides power to the motor and controls its speed. The source of the drive’s
start/stop and speed commands is determined by the Auto or Hand mode
selection of the drive’s keypad. Commands come from the control terminals
when the Auto mode has been selected or from the drive keypad when the
Hand mode has been selected.
Bypass mode
In the Bypass mode, the motor is powered by AC line power through the
bypass contactor. The user can switch to the Bypass mode by pressing the
Bypass key on the bypass keypad or by closing the Mode input contact. If the
Mode input contact is closed, the bypass switches to the Bypass mode and
does not respond to the Drive and Bypass keys. When the Mode input contact
is switched from closed to open, the bypass switches to the Drive mode but
can be controlled using the Drive and Bypass keys. Switching to Bypass mode
is done automatically if the user has selected the Automatic Transfer option
and a drive fault occurs.
The source of the bypass start/stop command is determined by the Hand or
Auto mode selection of the bypass keypad. Refer to the following descriptions
of the Hand mode and Auto mode.
Hand mode When the bypass is in the Bypass mode, the operator can manually start the
motor by pressing the Hand key. The motor will start and the Hand LED will
be illuminated green. In order to start the motor, the Enable contact must be
closed (green Enable LED) and any bypass fault must be reset.