Ground Fault Protection; Prevention Of Unexpected Start-Up (Option +Q950) - ABB ACS800-U1 Hardware Manual

Ground fault protection

The drive has ground fault protection in the motor and motor cable. This is not a
personal safety or a fire protection feature. The ground fault protection can be
disabled with a parameter, refer to the applicable firmware manual.
The EMC filter of the drive has capacitors between the main circuit and the frame.
These capacitors and long motor cables increase the ground leakage current and can
cause fault-current circuit breakers to function.

Prevention of unexpected start-up (option +Q950)

The drive can have an option for the prevention of unexpected start-up function
according to standards:
•
IEC/EN 60204-1:1997
•
ISO/DIS 14118:2000
•
EN 1037:1996
•
EN ISO 12100:2003
•
EN 954-1:1996
•
EN ISO 13849-2:2003
The Prevention of unexpected start-up (POUS) function disables the control voltage
of the power semiconductors, and prevents the drive from generating the AC
voltage required to rotate the motor. With this function, short tasks (such as
cleaning) or maintenance work on non-electrical parts of the machinery can be done
without switching off the AC power supply to the drive.
The operator activates the Prevention of unexpected start-up function by opening a
switch on a control desk. An indicating lamp on the control desk comes on to
indicate that the function is active. The switch can be locked out.
The user must install on a control desk near the machinery:
•
switching/disconnecting device for the circuitry. "Means shall be provided to
prevent inadvertent, and/or mistaken closure of the disconnecting device."
EN 60204-1:1997.
•
indicating lamp: on = the drive is disabled, off = drive can operate.
For connections to the drive, refer to the circuit diagram delivered with the drive.
WARNING! The Prevention of unexpected start-up function does not
disconnect the voltage of the main and auxiliary circuits from the drive.
Therefore maintenance work on electrical parts of the drive or the motor
can only be carried out after isolating the drive system from the main
supply.
The Prevention of unexpected start-up function is not intended for stopping the
drive. If the Prevention of unexpected start-up function is activated when the drive is
running, the control voltage of the power semiconductors is cut off and the motor
coasts to a stop.
For detailed instructions for installation, start-up, use and maintenance of the
Installation of the AGPS board (Prevention of unexpected start-up,
function, see
+Q950)
(page 75).
Planning the electrical installation 47