Emerson FPCBA, Инструкция по эксплуатации, Страница: 21 / 43

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bypass controller must see the customer “damper feedback” contact closed
(TB3-3) within that time to prevent the bypass controller from “faulting” and
preventing motor operation. The Bypass Keypad will annunciate the faulted
condition by flashing one or more of the button status LEDs that happened
to be on at the time of the fault. The bypass controller can be reset by
cycling the customer reset input, which will reset the 120 second timer and
retry motor operation.
Should the damper open initially, but sometime during operation the
damper feedback is lost, the Electronic bypass package will trip, stopping
the motor.
Switch 4:
With the VFD and Auto pushbuttons pressed on the Bypass
Keypad, Fire Alarm (switch 2) and Fireman’s Override (switch 4)
OFF
, upon
opening the fire alarm input (TB2-6) the unit goes into Bypass mode and the
Bypass Keypad will indicate a Fire Alarm. Eventually a VFD Fault will occur
and the input contactor will drop out.
Upon closing the fireman’s override input (TB3-4), the unit will go to Bypass
and Hand mode.
Re-closing the Fire Alarm input, and then opening the fireman’s override
input (TB3-4) will put the package back into VFD + Auto mode.
With Damper Control (switch 3)
OFF
: For normal operation mode a start
command is given, closing the Damper relay contacts. The unit then waits
for a contact closure from the Damper end switch indicating the Damper is
fully open. If the Damper feedback does not occur within 120 seconds, then
one or more of the LEDs on the board begin to flash indicating the damper
close timer has timed out without feedback being received.
In fireman’s override mode if the fireman’s override is enabled along with
the Damper control, at the end of the 120 seconds if there is no feedback
from the Damper End switch, the unit goes into bypass and operates as
described above.
3.4 Using the Additional Customer Inputs
In addition to the inputs described in the preceding sections, there are
three
other customer inputs for use in specific applications.
Safety
input (TB2-3): is normally closed, opening it causes the motor to
stop under all conditions, and will lock out all requests to start the motor. A
LED in the Alarm Display annunciates the status of the safety input. If there
are no safeties then a jumper must be installed to allow operation. To reset
the Electronic bypass package from a safety trip, the safety interlock must
be re-closed and the customer reset input (TB2-4) or the bypass keypad
OFF/RESET button must be cycled.
Remote bypass
input (TB3-1): can be used to override the keypad