Power Loss Ride-Through Function; Inverter Unit Control - ABB ACS800-07-0610-3 Hardware Manual

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Power loss ride-through function

The power loss ride-through function keeps the supply unit operative over an
unexpected input power break. The user can activate the function by setting the
power loss ride-through delay with the buttons on the DSSB board.
Note: Units with an air circuit breaker require an external UPS for the function to be
available.
The table below describes the operation of the function.
Duration of the
break
Shorter than
power loss ride-
through time.
Longer than
power loss ride-
through time.
The delay setting range is 0 to 40 seconds. For instructions on the setting, see page
28.

Inverter unit control

The inverter unit is controlled by an RDCU drive control unit located in the swing-out
frame. The RDCU is connected to the inverter modules by a fibre optic link,
distributed through an optical branching unit. In the inverter modules, the optic link
connects to the AINT board, the terminals of which are accessible through a hole on
the front panel of the module.
A control panel (type CDP-312R) is installed on the door of the drive. The CDP-312R
is the user interface of the inverters of the drive, providing the essential controls such
as Start/Stop/Direction/Reset/Reference, and the parameter settings for the drive
application program. See the Firmware Manual for further information.
Hardware description
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
What happens during the break
If the DC voltage drops less than 30%,
• the diode bridge stays in normal operating
mode, and
• the supply unit keeps the internal contactors
energised.
If the DC voltage drops more than 30%,
• the diode bridge switches into charging
mode and further into stand-by (only the
DSSB board is kept live by a backup
capacitor),
• relay output RO2 (Running) de-energises,
and
• the internal contactors open.
The supply unit stops and opens the main
contactors.
What happens after the
break
The supply unit resumes
rectifying automatically.
The supply unit "wakes up"
automatically and
• closes the internal
contactors,
• charges the DC bus,
• starts rectifying, and
• energises relay output RO2.
Operation continues only after
manual reset and restart.