Bussmann 170M3708 Class aR Hig...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$744.68
Bussmann 170M3708 High Speed Fuse

Bussmann 170M3708 Class aR High-Speed Fuse, 40A

(No reviews yet) Write a Review

Model: 170M3708
Selected Model is

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

$744.68
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 170M3708 Class aR High-Speed Fuse, 40A

The Bussmann 170M3708 is a Class aR high-speed fuse rated 40A RMS, engineered for fast-acting overcurrent protection in demanding DC power applications. Featuring a blade end X blade end connection and a 200 kAIC interrupt rating, this non-indicating fuse is designed for DC common bus systems, DC drives, and power converters/rectifiers where reliable semiconductor protection is critical. Bussmann backs this fuse with UL Recognized and IEC Rated certifications for dependable performance in industrial power distribution.

Key Features

  • Amperage Rating: 40A RMS current rating delivers dependable overcurrent protection for DC power circuits.
  • Class aR Construction: High-speed Class aR fuse design provides fast-acting response to protect sensitive semiconductor devices.
  • Connection Type: Blade end X blade end configuration for secure, direct mounting compatibility.
  • Interrupt Rating: 200 kAIC interrupt rating withstands high fault currents in demanding electrical systems.
  • Fuse Indicator: Non-Indicating design for standard fuse holder applications.
  • Watt Losses: 9W power dissipation rating supports efficient thermal performance.
  • Let-Through Energy: Pre-Arc I2t of 40 and Clearing I2t at 660V of 270 support precise overcurrent coordination.
  • Application: Suited for DC common bus, DC drives, and power converters/rectifiers.

Certifications & Compliance

  • CE Marked
  • RoHS Compliant
  • UL Recognized
  • IEC Rated

Technical Specifications

  • Amperage Rating: 40A
  • Application: DC common bus, DC drives, power converters/rectifiers
  • Class: Class aR
  • Clearing I2t: Clearing at 660V: 270
  • Connection: Blade end X blade end
  • Current Rating: 40A RMS
  • Fuse Indicator: Non Indicating
  • Interrupt Rating: 200 kAIC
  • Packaging Type: Standard
  • Pre Arc I2t: 40
  • Watt Losses: 9W
  • Product Type: Square body, US style -FU/115 without indicator
  • Product Details: Square body, US style -FU/115 without indicator
  • Product Length: 5.433 IN
  • Product Height: 2.087 IN
  • Product Weight: 1.6456 LB
  • Product Width: .315 IN

Typical Applications

  • DC Common Bus Power Systems
  • DC Drive Overcurrent Protection
  • Power Converter and Rectifier Circuits
  • Semiconductor Device Protection
  • Industrial Power Distribution

Why Bussmann?

Bussmann fuses are engineered for reliable, code-compliant performance in demanding industrial power applications. With UL Recognized and IEC Rated certifications, plus CE Marked and RoHS Compliant construction, the 170M3708 Class aR high-speed fuse delivers the fast-acting overcurrent protection and high 200 kAIC interrupt rating that DC drive and power converter systems depend on.

Manufacturer Resources

Product Specs

Amperage Rating:
40A
Application:
DC common bus, DC drives, power converters/rectifiers
Class:
Class aR
Clearing I2t:
Clearing at 660V: 270
Connection:
Blade end X blade end
Current Rating:
40A RMS
Fuse Indicator:
Non Indicating
Interrupt Rating:
200 kAIC
Packaging Type:
Standard
Pre Arc I2t:
40
Watt Losses:
9W
Product Group:
Fuses
Department:
Electrical
Product Subgroup:
Other Fuses
Product Type:
Fuse
Product Length:
5.433 IN
Product Details:
Square body, US style -FU/115 without indicator
Product Height:
2.087 IN
Product Weight:
1.6456 LB
Product Width:
.315 IN

Bussmann 170M3708 – Frequently Asked Questions

1) Will a Bussmann 170M3708 protect the semiconductors in a DC drive, or do I need a standard branch-circuit fuse?
The 170M3708 is a Class aR high-speed fuse, which is a semiconductor protection fuse, not a branch-circuit or motor-circuit fuse. Class aR is partial-range: it clears short circuits fast enough to save diodes, SCRs and IGBTs, but it is not intended to be your only overload protection. Bussmann lists it for DC common bus, DC drives and power converters/rectifiers. If you need overload plus short-circuit protection on a general feeder, use a branch-rated class fuse instead and keep the aR on the semiconductor stack.
2) How does the Bussmann 170M3708 mount, and will it drop into a clip-style fuse holder?
It will not. The 170M3708 is a square body US style fuse with a blade end X blade end connection, so it bolts down onto flat terminal pads at each end rather than pushing into clips. Body size is 5.433 in long by 2.087 in high by .315 in wide, and it weighs 1.6456 lb, so plan on a bolted bus or a square body mounting base with matching centers.
3) What fault current can the 170M3708 safely interrupt?
200 kAIC. That covers the available fault current at most industrial service entrances and DC bus links, so the fuse is not the weak link on a stiff supply. The 40A RMS rating is the continuous current side of the spec, not the fault side, so size the fuse to the converter's RMS current and let the 200 kA rating handle the short circuit.
4) What I2t values do I use to coordinate the 170M3708 with my rectifier diodes?
Pre-arc I2t is 40 and clearing I2t at 660V is 270. Compare the clearing figure against the I2t withstand of the diode or SCR you are protecting: the device rating has to exceed 270 at your operating voltage for the fuse to save it. The pre-arc value is what you use when coordinating with an upstream or downstream fuse so the 170M3708 clears first.
5) Does the Bussmann 170M3708 have a blown-fuse indicator or microswitch option?
No. This one is the non-indicating version, catalogued as US style -FU/115 without indicator. There is no striker pin or visual flag, so if your panel relies on a microswitch-actuated alarm contact, this fuse will not trip it. Use a holder with its own monitoring, or specify an indicating version of the square body fuse.
6) Is the Bussmann 170M3708 acceptable for a CE-marked export panel?
Yes. The 170M3708 is CE Marked, RoHS Compliant, UL Recognized and IEC Rated, so it can be specified in equipment built to IEC standards as well as UL-recognized assemblies. Note UL Recognized is a component listing, meaning it is evaluated for use inside listed equipment rather than as a standalone listed device.
7) I need to reorder the exact fuse in a DC drive. What part number do I ask for?
Bussmann 170M3708, a 40A Class aR square body high-speed fuse with blade end X blade end terminals and no indicator. The 170M series number and the amp rating both have to match, since the same body size is built in a range of amperages and in indicating and non-indicating versions.
8) How much heat does the 170M3708 put into an enclosure?
Watt loss is 9W at rating. For a multi-fuse DC bus assembly, multiply that by the number of fuses when you size enclosure ventilation, and derate the fuse if the internal ambient runs hot or if the fuse is mounted in still air without bus bar heat sinking.
How fast can I get the Bussmann 170M3708 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 170M3708 come with a warranty?
Absolutely. The Bussmann 170M3708 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 170M3708?
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 170M3708 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.
!