Bussmann FRS-R Fusetron Class ...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$73.00
Bussmann FRS-R Fusetron Class RK5 Time-Delay Fuse

Bussmann FRS-R Fusetron Class RK5 Time-Delay Fuse

(No reviews yet) Write a Review

Model: FRS-R-1-1/4

In Stock (leaves warehouse same day if ordered before 3pm ET)

$73.00
Adding to cart… The item has been added
Free Shipping on orders over $199
We price match and offer bulk discounts! Click Add to Quote. It's quick and easy.
✨
Earn points with this purchase! You can redeem points for giftcards, iPads, XBox's and more. View Rewards
Free Keying on all locks
You may also like

Bussmann FRS-R-3/10 Fusetron Class RK5 Time-Delay Fuse

The Bussmann FRS-R-3/10 Fusetron is a dual-element, current-limiting time-delay fuse rated 3/10A, engineered for Class RK5 applications requiring dependable motor and circuit protection. Rated 600 Vac / 300 Vdc with a ferrule end x ferrule end connection, this fuse pairs a 200 kAIC interrupt rating at 600 Vac (20 kAIC at 300 Vdc) with a 10s at 500% response time to ride through harmless overloads while clearing true faults quickly. It is built for combination starters, motor control centers, machinery disconnects, and power panelboards where reliable, code-compliant overcurrent protection is required.

Key Features

  • Amperage Rating: 3/10A for precise low-current circuit protection.
  • Class RK5 Construction: Current-limiting, time-delay fuse design suited to motor and branch-circuit applications.
  • Dual-Element Design: Two internal elements let the fuse absorb temporary overloads such as motor inrush without nuisance opening.
  • Ferrule End x Ferrule End Connection: Simplifies installation into standard fuse holders and disconnect switches.
  • Voltage Rating: 600 Vac, 300 Vdc for use across AC and DC electrical systems.
  • Interrupt Rating: 200 kAIC at 600 Vac and 20 kAIC at 300 Vdc for high fault-current withstand capability.
  • Response Time: 10s at 500% overload, delivering true time-delay performance that rides through motor inrush.
  • Non-Indicating Design: Standard fuse body without a blown-fuse indicator window.

Technical Specifications

  • Amperage Rating: 3/10A
  • Application: Combination starters, motor control centers, machinery disconnects, power panelboards
  • Class: Class RK5
  • Connection: Ferrule end X ferrule end
  • Fuse Indicator: Non Indicating
  • Interrupt Rating: 200 kAIC at 600 Vac, 20 kAIC at 300 Vdc
  • Number Of Elements: Dual
  • Packaging Type: Standard
  • Response Time: 10s at 500%
  • Voltage Rating: 600 Vac, 300 Vdc
  • Product Type: Current-limiting, time delay
  • Product Length: .81 IN
  • Product Details: Current-limiting, time delay
  • Product Diameter: .81 IN
  • Product Height: 5 IN
  • Product Weight: .15 LB
  • Product Width: .81 IN

Typical Applications

  • Combination Starters
  • Motor Control Centers
  • Machinery Disconnects
  • Power Panelboards
  • Industrial and Commercial Overcurrent Protection

Why Bussmann?

Bussmann engineers the FRS-R Fusetron series for demanding motor control and branch-circuit environments, backing the 3/10A Class RK5 fuse with a 200 kAIC interrupt rating and a proven dual-element time-delay design. This construction helps electricians and facility teams protect combination starters, motor control centers, and panelboards from both overloads and short circuits with confidence in reliable, code-compliant performance.

Product Specs

Connection:
Ferrule end X ferrule end
Fuse Indicator:
Non Indicating
Product Subgroup:
Fuses
Class:
Class RK5
Interrupt Rating:
200 kAIC at 600 Vac, 20 kAIC at 300 Vdc
Product Details:
Current-limiting, time delay
Product Height:
5 IN
Product Length:
.81 IN
Product Weight:
.15 LB
Product Group:
Circuit Protection
Product Width:
.81 IN
Product Diameter:
.81 IN
Packaging Type:
Standard
Voltage Rating:
600 Vac, 300 Vdc
Response Time:
10s at 500%
Department:
Electrical
Product Type:
Time-Delay Fuse
Number Of Elements:
Dual

Bussmann FRS-R-1-1/4 – Frequently Asked Questions

1) Will a Bussmann FRS-R fuse fit a standard Class R fuse holder or 600V disconnect switch?
The FRS-R Fusetron is a ferrule end x ferrule end fuse measuring .81 inch in diameter, so it drops into standard ferrule-style Class R clips in disconnects and fuse holders rather than needing bolt-on lugs. Rated 600 Vac / 300 Vdc, so it suits 600V and below switches. Ferrule fuses are a push-in fit, so the clip spacing in your holder has to match the fuse body length.
2) Which amp ratings does the Bussmann FRS-R Fusetron come in?
Four low-amp ratings are offered: 1/4 A (FRS-R-1/4), 3/10 A (FRS-R-3/10), 4/10 A (FRS-R-4/10), and 1-1/4 A (FRS-R-1-1/4). These are fractional-amp fuses for control circuits and small loads, not for feeder or large motor branch protection.
3) Will a time-delay FRS-R fuse hold through motor inrush without nuisance blowing?
That is what the dual-element construction is for. The Fusetron FRS-R carries a 10 second response at 500% of rating, so a short inrush or starting surge passes without opening the fuse, while a genuine short circuit is cleared by the current-limiting element. If you need instantaneous clearing instead of ride-through, a fast-acting fuse is the wrong-direction choice here.
4) Is the FRS-R rated for a 200,000 amp available fault current service?
Yes. The FRS-R Fusetron interrupts 200 kAIC at 600 Vac, and 20 kAIC at 300 Vdc. On DC circuits plan around the lower 20 kAIC figure, not the AC number.
5) Can I use a Class RK5 fuse where the panel is marked for Class R fuses?
Class RK5 is a Class R fuse and fits Class R rejection clips. What it will not do is substitute for a specified RK1: RK1 has tighter current-limiting let-through, so if the equipment label or drawing calls for RK1, an RK5 is not an equal swap. Going the other way, an RK1 can replace an RK5.
6) Can the FRS-R be used on a DC circuit?
Yes, up to 300 Vdc, with a 20 kAIC interrupting rating on DC. On AC it is good to 600 Vac with 200 kAIC. Do not apply it above 300 volts DC.
7) Does the FRS-R have a blown fuse indicator?
No. The Fusetron FRS-R is a non-indicating fuse, plain body with no indicator window or pop-up pin. Troubleshooting means pulling the fuse and checking continuity, so if your crew relies on visual blown-fuse checks in a motor control center, spec an indicating type instead.
8) What are these fractional-amp Fusetron fuses typically used for?
Low-amp FRS-R ratings like 1/4 A and 4/10 A usually protect control transformer secondaries, instrumentation, and small control circuits inside combination starters, motor control centers, machinery disconnects, and power panelboards. For the motor branch itself you would be sizing much higher in the FRS-R range.
How fast can I get the Bussmann FRS-R-1-1/4 delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Bussmann FRS-R-1-1/4 come with a warranty?
Absolutely. The Bussmann FRS-R-1-1/4 is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Bussmann FRS-R-1-1/4?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Bussmann FRS-R-1-1/4 from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
!