Select a magnetic circuit breaker or fuse rated at 1.5 times the input current rating of the VFD. For the Micro Series, SM and SM-Plus Series, the minimum fuse size should be 10 amps, regardless of the input current. The 10 amp minimum is required to accommodate the inrush during power up. The VFD provides motor protection. Bussmann current limiting type fuses with low I 2 T values, rated 200,000 AIC are recommended. Similar fuses with equivalent ratings by other manufacturers may also be acceptable.
Fuse types are listed below:
- For 240 / 120 Vac and 240 / 200 Vac models, use a KTK-R or JJN type, 250 Vac rated fuse.
- For 480 / 400 Vac models, use a KTK-R or JJS type, 600 Vac rated fuse.
- For 590 / 480 Vac models, use a KTK-R or JJS type, 600 Vac rated fuse.