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3.7.5 AUTO mode
In the VFD AUTO (automatic mode), a building automation system or other
external device is required to supply start/stop and speed reference
information to the Electronic bypass package. During AUTO mode operation,
the Electronic bypass keypad remains enabled for stopping, operation mode,
and bypass selection functions. AUTO mode can control both VFD and
BYPASS operation modes
To place in AUTO mode, press the VFD button. Then press the AUTO button.
The VFD, AUTO and input and output contactor LEDs will be illuminated. The
RUN LED will not illuminate until the user supplied (TB2-5) run contact closes.
Motor speed is controlled by the user supplied 4–20 mA reference signal. See
section 4.3
and 4.4 if a 0–10 Vdc reference is to be used.
To place in BYPASS AUTO mode, press the BYPASS button. Then press the
AUTO button. The BYPASS and AUTO LEDs will be illuminated. The bypass
contactor and RUN LEDs will not illuminate until the user supplied (TB2-5) run
contact closes
To exit the AUTO mode, press the OFF/RESET button once on the Electronic
bypass keypad. The AUTO and RUN LEDs will turn off. Pressing the
OFF/RESET button again will turn off the VFD or BYPASS operation LEDs.
3.8 Bypass Modes of the Electronic bypass
There are three modes of operation for bypassing the VFD and operating on
full line power.
MANUAL Bypass
Manual bypass operation
AUTOMATIC Bypass
Automatic bypass on VFD fault
EMERGENCY bypass
Emergency, manual bypass
3.8.1 MANUAL Bypass
In the manual bypass mode, the motor begins bypass operation immediately
upon selecting HAND mode or upon the user supplied contact closure in
AUTO mode. The motor will stay in bypass until the user chooses to leave
either HAND or AUTO mode. Bypass is also available while in the TEST
mode of operation.
To place in manual bypass mode, press the BYPASS button to enter the
BYPASS mode. When the BYPASS LED illuminates, press either the HAND
or AUTO button. When the HAND button is pressed the bypass contactor will
energize and the motor will immediately start across the line. When the AUTO
button is pressed, the bypass contactor will not energize until the user
supplied (TB2-5) run contact is closed, then the bypass contactor will energize
and the motor will immediately start across the line
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