B-Line 5HLE-20E Current Limiting Fuse

The 5HLE-20E is a medium voltage current limiting fuse rated to 5.5 kV maximum, so it suits 2.4 kV, 4.16 kV and 4.8 kV class distribution circuits. It is not a low voltage fuse and has no place in a 480V panel.

E-rated means the fuse follows the standard E-rating melting characteristic, so a 20E fuse carries 20 amps continuously and its time-current curve is interchangeable with any other manufacturer's 20E of the same class. For transformer primary protection you size the E rating to the transformer's full load primary amps plus inrush allowance, not to the secondary load.

Interrupting rating on the 5HLE-20E is 63 kAIC, which covers most utility and industrial medium voltage services at 5 kV class. Check the available short circuit current at the fuse location from your coordination study; anything at or below 63 kA is within rating.

No. The HLE current limiting fuse ships as the fuse itself, and B-Line notes that mountings are a factory consult item. Order your clips, mounting brackets, or fuse holders separately and match them to the fuse barrel and your enclosure.

Yes. The HLE series 5HLE-20E is rated for indoor and outdoor use, so it can go in weatherproof enclosures, pad mount gear, or outdoor switch structures as well as indoor switchgear.

Single barrel. That keeps the envelope smaller than a parallel multi barrel unit of the same class, which matters when you are fitting it into an existing clip spacing or a tight compartment.

Replace all three. A current limiting fuse that has cleared a fault has put thermal and mechanical stress on the companions in the same three phase set, and mixed age fuses can drift apart on their melting curves. Standard practice in an MRO or utility crew is to change the full set of 20E fuses at once so the bank stays matched.

A current limiting fuse clears the fault before the first peak, cutting the let-through energy and the mechanical stress on downstream gear, and it does so without venting arc products, which is why it can be used inside enclosed switchgear. An expulsion fuse lets the full fault current flow for at least a half cycle and vents hot gas, so it needs open air clearance. The 5HLE-20E is the current limiting type at 5.5 kV and 63 kAIC.