Protecting The Motor And Motor Cable In Short-Circuits; Protecting The Drive And The Input Power And Motor Cables Against Thermal Overload; Protecting The Motor Against Thermal Overload; Connecting Drive Modules To A Common Dc System - ABB ACQ580-34 Hardware Manual

56 Guidelines for planning the electrical installation
data. The fuses for the drive protection will restrict drive damage and prevent damage to
adjoining equipment in case of a short-circuit inside the drive.
Note: If the fuses for the drive protection are placed at the distribution board and the input
cable is dimensioned according to the nominal input current of the drive given in the technical
data, the fuses protect also the input cable in short-circuit situations, restrict drive damage
and prevent damage to adjoining equipment in case of a short-circuit inside the drive. No
separate fuses for the input cable protection are needed.
￭

Protecting the motor and motor cable in short-circuits

The drive protects the motor cable and motor in a short-circuit situation when the motor
cable is sized according to the nominal current of the drive. No additional protection devices
are needed.
￭ Protecting the drive and the input power and motor cables against
thermal overload
The drive protects itself and the motor cables against thermal overload when the cables are
dimensioned according to the nominal current of the drive. No additional thermal protection
devices are needed.
WARNING!
If the drive is connected to multiple motors, use a separate circuit breaker or fuses
for protecting each motor cable and motor against overload. The drive overload
protection is tuned for the total motor load. It may not trip due to an overload in
one motor circuit only.
￭

Protecting the motor against thermal overload

According to regulations, the motor must be protected against thermal overload and the
current must be switched off when overload is detected. The drive includes a motor thermal
protection function that protects the motor and switches off the current when necessary.
Depending on a drive parameter value, the function either monitors a calculated temperature
value (based on a motor thermal model) or an actual temperature indication given by motor
temperature sensors.
The motor thermal protection model supports thermal memory retention and speed sensitivity.
The user can tune the thermal model further by feeding in additional motor and load data.
The most common temperature sensors are:
• motor sizes IEC180...225: thermal switch, for example Klixon
• motor sizes IEC200...250 and larger: PTC or Pt100.
See the firmware manual for more information on the motor thermal protection function.
￭

Connecting drive modules to a common DC system

Do not connect the drive module to a common DC system
WARNING!
The UDC+ and UDC- terminals of the drive module must not be used for any other
than optional external brake chopper connection. Drives connected to a common
DC system will get damaged.