ABB ACS880-04F-504A-3, Руководство по оборудованию

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WARNING!
If the drive is connected to multiple motors, use a separate overload protection
for each motor cable and motor. The drive overload protection is tuned for the
total motor load. It may not detect an overload in one motor circuit only.
North America: The local code (NEC) requires an overload protection and a
short-circuit protection for each motor circuit. Use, for example:
• manual motor protector
• circuit breaker, contactor and overload relay or
• fuses, contactor and overload relay.
￭
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 sensor types are PTC or Pt100.
For more information, see the firmware manual.
￭
Protecting the motor against overload without thermal model or
temperature sensors
Motor overload protection protects the motor against overload without using motor
thermal model or temperature sensors.
Motor overload protection is required and specified by multiple standards including
the US National Electric Code (NEC) and the common UL/IEC 61800-5-1 standard in
conjunction with UL/IEC 60947-4-1. The standards allow for motor overload protection
without external temperature sensors.
The protection feature of the drive allows the user to specify the class of operation
in the same manner as the overload relays are specified in standards UL/IEC 60947-4-1
and NEMA ICS 2.
The motor overload protection supports thermal memory retention and speed
sensitivity.
For more information, see drive firmware manual.
Protecting the drive against ground faults
The drive is equipped with an internal ground fault protective function to protect the
unit against ground faults in the motor and motor cable. This function is not a
personnel safety or a fire protection feature. See the firmware manual for more
information.
Guidelines for planning the electrical installation 75