Emerson HVAC Drive H300, Руководство по установке и пусконаладке

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24 Electronic Bypass Controller Installation and Commissioning Guide
4.3 Using the Electronic Bypass Configuration Switches
The bypass configuration switches are a group of four switches that are used to tailor
the following:
1 2 3
4
O N
Automatic Bypass
Fire Alarm
Damper Control
Fireman’s Override
Note: “ON” disables function
Switch 1: Enables or disables the automatic bypass function. With switch 1 in the ON
position and the electronic bypass package operating in VFD Mode, a VFD fault will
cause both the operation and run modes to be canceled (stopping the motor) and the
VFD FAULT LED to illuminate in the Alarm Display.
With switch 1 in the OFF position, a VFD fault will cause the bypass contactor to close,
keeping the motor running on line power. As with the switch 1 ON configuration, the
drive fault will be displayed in the Alarm Display. See section 3.8.2.
Switch 2:
Controls the bypass response to a fire alarm condition. The OFF (active)
position equals “Purge”; the ON position equals an “All Stop” position.
The default ON position of switch 2 causes the opening of the fire alarm input (TB2-6)
to stop the motor independent of whether it was being run by the VFD or the line.
When the motor is stopped in this situation, the previous operating state of the
electronic bypass package will be restored by removing the fire alarm signal and
cycling the customer reset input.
It is recommended that VFD parameter “Catch a Spinning Motor”, be set to 1 if the
fire alarm input is used.
With switch 2 in the active OFF position, the bypass will attempt to run the system “to
destruction” in the event of fire. Receiving a fire alarm signal in this mode will force
the unit to bypass, causing the motor to operate off the AC line. The motor cannot
be stopped locally or by external contacts in this mode. The keypad will appear to be
“locked out”. Only cycling power to the bypass will return it to normal operation.
Switch 3: Used in damper applications where it is required to make sure a damper
has opened in order to run the motor. The default ON position of Damper Control
(switch 3) disables damper mode. With the Damper Mode set in the enabled OFF
position, when the motor is told to start (either on the VFD or by the bypass from the
AC line) a 120 second timer is started. The bypass controller must see the customer