Relay Contact (Digital) Inputs; Automatic Transfer Feature; Bypass Control Board Inputs And Outputs; Run Enable (Di2) - ABB ACH550 series User Manual

38
Hand or Auto mode, the motor will start across the line as soon as power is applied.
If the system is in the Drive mode with the drive in the Auto mode, the motor will start
on the drive as soon as power is applied.

Automatic Transfer Feature

When the Automatic Transfer feature is selected, the system switches to Bypass
mode and the motor is automatically transferred to line power if the drive trips out on
a protective trip. If automatic restart has been enabled in the drive, the drive will
attempt to automatically restart before the motor is transferred to line power. The
Automatic Transfer function can be enabled through the bypass control panel. The
Automatic Transfer indication is provided on the bypass control panel. The control
panel display will continuously flash an alarm to indicate the system has
automatically transferred to Bypass. The bypass event log will also record this event.

Bypass Control Board Inputs and Outputs

The bypass control board has five programmable and one fixed relay contact
(digital) inputs and five programmable relay outputs that are available for connection
to external control circuits. The internal 24VDC supply is normally used in
conjunction with the relay contact inputs. The input and output functions are
described below. Refer to "Installation" for additional information and connection
instructions.

Relay Contact (Digital) Inputs

All Relay Contact (Digital) Inputs with the exception of the Override 1 "Smoke
Control" Input can be configured to any one of three (3) conditions.
1. "Digital Input" (DI), in which case the bypass system will react to the defined input
function during normal operation.
2. "Not Selected", in which case the bypass system will ignore the defined input
function as bypass control, but will continue to pass the operating state of the digital
input through serial communications to the building automation system.
3. "Comms", in which case the bypass system will react to the defined input function
over serial communications during normal operation. The bypass system will ignore
the digital input as a defined input function, but will continue to pass the operating
state of the digital input over serial communications to the building automation
system.
Start/Stop (DI1)
The Start/Stop input is connected to a normally open contact that starts and stops
the system. When the bypass is in the Drive mode and the drive is in the Auto mode,
the Start/Stop input contact controls the motor by starting and stopping the drive.
When the bypass is in the Bypass mode and Auto is indicated on the bypass control
display, the Start/Stop input contact controls the motor by controlling the bypass
contactor.

Run Enable (DI2)

The Run Enable input is connected to the series combination of any external
normally closed permissive contacts, such as damper end switches, that must be
closed to allow the motor to run. If any of these external contacts are open while a
Overview of Bypass Functionality
E-Clipse Bypass Configurations for ACH550 Drives