Danfoss VLT, Pocket Manual, Page: 36 / 64

36 VLT ® Soft Starter Pocket Guide
Type 2 protection requires that in the event of a short circuit on the
output of a soft starter the fault must be cleared without risk of injury
to personnel or damage to the soft starter.
Type 2 protection is provided by semiconductor fuses, which must be
able to carry motor start current and have a total clearing I2t less than
the I
2 t of the soft starter SCRs.
Semiconductor fuses for Type 2 circuit protection are additional to HRC
fuses or MCCBs that form part of the motor branch circuit protection.
Refer to the soft starter’s Design Guide for semiconductor fuse
recommendations.
Short Circuit Protection: What is required for Type 2
short circuit protection of a soft starter?