Nidec D3-0023-B, Руководство пользователя

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Digistart D3: User Guide
Issue: G
4.4.2 Short Circuit Protection Devices (SCPD)
Fuses may be installed to protect the soft starter or the installation.
Type 1 Coordination
Type 1 coordination requires that, in the event of a short circuit on the output side of a soft starter, the fault must be
cleared without risk of injury to personnel. There is no requirement that the soft starter must remain operational after
the fault.
HRC fuses (such as Ferraz/Mersen AJT fuses) can be used for Type 1 coordination according to IEC 60947-4-2
standard.
Type 2 Coordination
Type 2 coordination requires that in the event of a short circuit on the output side of a soft starter, the fault must be
cleared without risk of injury to personnel or damage to the soft starter.
Semiconductor fuses for Type 2 circuit protection are additional to HRC fuses or MCCBs that form part of the motor
branch circuit protection.
CAUTION
Adaptive Control controls the motor's speed profile, within the programmed time limit. This may result in a
higher level of current than traditional control methods.
CAUTION
DC Brake: A high brake torque setting can result in peak currents up to motor DOL being drawn while the
motor is stopping. Ensure protection fuses installed in the motor branch circuit are selected appropriately.
CAUTION
Integral solid state short circuit protection does not provide branch circuit protection. Branch circuit
protection must be provided in accordance with the National Electrical Code and any additional local
codes.
4.4.3 UL Short Circuit Ratings
Short circuit current ratings (SCCR) are available for 480 VAC and 600 VAC installations.
• 480 VAC circuits
For UL compliant installation, select a fuse that meets the specified fuse class and maximum fuse rating.
• 600 VAC circuits
For UL compliant installation, the starter can be protect by either fuses or a circuit breaker as specified in the
following tables.