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FRN-R-40
FRN-R-40
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FRN-R-40 Specifications
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FRN-R-40, Eaton, Bussmann Series, type FRN-R, Class RK5, low voltage, 1 barrel, 0.81" diameter, 40A, 250Vac/125Vdc, 200kA@250V, dual element, current-limiting, time-delay fuses
| Manufacturer | Eaton | Subcategory | Low Voltage |
| Family | Bussmann Series | ||
| Manufacturer | Eaton | ||
| Subcategory | Low Voltage | ||
| Family | Bussmann Series |
Electrical.com is NOT an authorized distributor for Square D and therefore the manufacturer’s warranty does not apply. This product does include an Electrical.com 2 year warranty.
We can test, inspect and repair your FRN-R-40. All repairs include a 2-Year Electrical.com Warranty.
The FRN-R-40 is part of Eaton’s Bussmann series Fusetron™ FRN‑R Class RK‑5 line of dual‑element, current‑limiting, time‑delay fuses engineered for robust overcurrent protection in low‑voltage AC and DC circuits. These fuses are designed to handle temporary overloads and inrush currents-such as those seen during motor starts or transformer energizing-without nuisance opening, while still providing reliable short‑circuit interruption when needed. The FRN‑R series is rated for 250 VAC and 125 VDC service and meets UL 248‑12 Class RK‑5 and CSA C22.2 No. 248.12 standards, reflecting trusted industry safety and performance credentials.
The FRN-R-40 is rated at 40 amps with a high interrupting capacity-typically 200 kA RMS at 250 VAC and 20 kA at 125 VDC-ensuring it can safely clear severe fault conditions in properly designed systems. Its dual‑element construction combines a time-delay overload element with a fast-acting short-circuit element, enabling it to withstand brief surges up to five times its rating for at least ten seconds before opening. This time‑delay characteristic improves coordination with upstream protective devices and helps prevent unnecessary downtime in industrial, commercial, and motor control applications.
Originally manufactured under the Cooper Bussmann brand, which Eaton acquired and now markets globally under the Eaton Bussmann division, the FRN‑R series continues a legacy of reliable fuse technology known for energy efficiency and rugged performance. Bussmann Series products like the FRN-R-40 find broad use in motor branch circuits, control panels, lighting feeders, and transformer protection schemes where both overload tolerance and current‑limiting characteristics are critical. Eaton’s ongoing support and extensive distribution network make these fuses widely accessible for design engineers, panel builders, and maintenance professionals.
Purchase the FRN-R-40 at Electrical.com, your reliable partner for industrial and commercial electrical products. Our selection includes fuses and accessories from manufacturers like Eaton, and Copper Bussmann, backed by a dedicated sales team ready to assist with technical questions, product selection, and support.