Time Delay Class CC Fuses

Eaton Bussmann’s FNQ-R series are Class CC, dual-element, time-delay fuses are designed to ride through the high inrush typical of control transformers and small motors while still providing fast, current-limiting short-circuit protection. Key specs include 600 Vac ratings across the line (selected ratings also 300 Vdc—commonly the 15 A and 20 A sizes), available ampere ratings from ¼–30 A, and a 200 kA interrupting rating at 600 Vac (20 kA at 300 Vdc on the 15–20 A parts). The rejection-style ferrule body (approx. 13/32″ × 1-1/2″ / 10.3 mm × 38.1 mm) ensures compatibility with Class CC holders and prevents misapplication. FNQ-R fuses provide substantially improved current limitation versus general-purpose fuses and meet UL 248-4 Class CC requirements; typical time-delay performance allows ~12 s at 200% of rated current, helping avoid nuisance openings on inrush.

The FNQ-R fuses are a go-to choice for protecting control-circuit transformers, PLC and control-power supplies, solenoids and contactor coils, and small motor branch circuits where ride-through on startup is critical but short-circuit energy must be tightly limited. They’re widely applied in industrial control panels, HVAC and refrigeration controls, machine tools, material-handling equipment, and general branch-circuit line protection, especially where panel space is tight and a 600 Vac, 200 kAIC, rejection-style Class CC format is preferred. Pair them with matching Class CC fuse blocks/holders to maintain the rejection feature and interrupting ratings and select the amp rating to satisfy NEC/UL sizing while accommodating transformer/motor inrush.