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BUSSMANN Fuse: Class RK5, FRN-R Series, Time-Delay, 4 A, 250 V AC, 125 V DC - Time-Delay Cylindrical Fuses
BUSSMANNTime-Delay Cylindrical Fuses

BUSSMANN Fuse: Class RK5, FRN-R Series, Time-Delay, 4 A, 250 V AC, 125 V DC

The BUSSMANN FRN-R-4 is a Class RK5, time-delay cylindrical fuse from the FRN-R Series, rated 4 A at 250 V AC and 125 V DC, non-indicating. 3G Electric interprets your demand for this OEM-specified overcurrent…

SKU 3G-OTH-28681

Also listed as: FRNR4 · FRN R 4

Brand
BUSSMANN
Item
Fuse: Class RK5, FRN-R Series, Time-Delay, 4 A, 250 V AC, 125 V DC
Category
Time-Delay Cylindrical Fuses
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

BUSSMANN
Manufacturer Part Number
FRN-R-4
Series
FRN-R
Type
FRN-R Series, Time-Delay, 4 A, Non-Indicating
AC
250 V
DC
125 V

Technical Documents

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BUSSMANN Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The BUSSMANN FRN-R-4 is a Class RK5, time-delay cylindrical fuse from the FRN-R Series, rated 4 A at 250 V AC and 125 V DC, non-indicating. 3G Electric interprets your demand for this OEM-specified overcurrent protection component, sourcing it across 14 industrial departments — with specialist depth in controls to support your electrical system requirements.

Frequently Asked Questions

What is the BUSSMANN FRN-R-4 fuse used for?

The BUSSMANN FRN-R-4 is a Class RK5 time-delay fuse rated 4 A, 250 V AC / 125 V DC. It protects motor circuits, lighting, and control transformers against short circuits and sustained overloads. Its time-delay characteristic prevents nuisance opening during inrush currents, making it suitable for industrial and commercial power distribution.

What are the specifications of the BUSSMANN FRN-R-4 fuse?

The BUSSMANN FRN-R-4 is a Class RK5, time-delay, non-indicating cylindrical fuse. It is rated 4 A, 250 V AC and 125 V DC. It belongs to the FRN-R series and is manufactured under part number FRN-R-4. It provides branch-circuit protection with a 200 kA interrupting rating at rated voltage.

Where to buy BUSSMANN FRN-R-4 fuses worldwide?

3G Electric supplies BUSSMANN FRN-R-4 fuses worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this Class RK5 time-delay fuse. We source genuine BUSSMANN components for industrial maintenance and OEM applications.

How to select the right BUSSMANN FRN-R series fuse for a motor circuit?

Select a BUSSMANN FRN-R series fuse by matching the voltage (250 V AC or 125 V DC) and current rating (e.g., 4 A for the FRN-R-4) to the motor full-load amps. Use the time-delay characteristic to handle startup inrush without nuisance tripping. Always consult the motor nameplate and local code for proper sizing.

Used in

Common applications for BUSSMANN
Industrial motor control centers — BUSSMANN LPT series Class T time-delay fuses for branch circuit protection
Semiconductor protection in variable frequency drives — BUSSMANN FWA series fast-acting bolt-on fuses rated 150 V AC/DC
Automotive auxiliary circuit protection — BUSSMANN CB222 series Type II circuit breakers in 12 V DC systems
Control panel overcurrent protection — BUSSMANN FNA series midget time-delay indicating fuses for instrumentation
Main feeder protection in power distribution — BUSSMANN KLU series Class L time-delay bolt-on fuses up to 650 A
Fuse replacement in existing panels — BUSSMANN S-8301-1-R fuse block accepting 3AG and other glass/ceramic fuses

BUSSMANN Products

3G Electric supplies BUSSMANN time-delay cylindrical fuses. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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