Mersen 636 Class H & K Fuse Re...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$106.96
$42.39
Mersen 636 Class H & K Fuse Reducer - H & K

Mersen 636 Class H & K Fuse Reducer, 600V Rated

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Model: 636

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

$106.96
$42.39
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Mersen 636 Class H & K Fuse Reducer, 600V Rated

The Mersen 636 Class H & K Fuse Reducer is built for industrial and commercial electrical systems that require dependable fuse holder reduction between Class H, K, and R fuse types. Rated 600 VAC and 600 VDC with a 50 kA SCCR, this fuse reducer is UL Listed and CSA Certified, making it a reliable choice for panelboards and power distribution equipment where code-compliant performance is essential.

Key Features

  • Voltage Rating: 600 VAC and 600 VDC for use across a wide range of power distribution systems.
  • Short-Circuit Current Rating: 50 kA SCCR supports use in demanding fault-current environments.
  • Fuse Class Compatibility: Reduces between Class H, K, and R fuse types for flexible panel and disconnect configurations.
  • UL Listing: UL Listed under Guide No. IZZR, Certification E105670 IZZR.E105670, for code-compliant installations.
  • CSA Certification: CSA Certified under 6225-01 207417 for use in CSA-jurisdiction installations.
  • Standards Compliance: Meets 250V and 600V Class H, K, and R UL Listed Guide No. IZZR and CSA certification requirements, plus 600V Class J UL Listed standards.

Certifications & Compliance

  • UL Listed - Guide No. IZZR, Certification E105670 IZZR.E105670
  • CSA Certified - 6225-01 207417
  • Complies with 250V and 600V Class H, K, and R, and 600V Class J UL Listed standards

Technical Specifications

  • Ac Voltage: 600 VAC
  • Ce Conformity: Consult Technical Services
  • Csa Certification: 6225-01 207417
  • Dc Voltage: 600 VDC
  • Lead Free: Consult Technical Services
  • Rohs Compliant: Consult Technical Services
  • Sccr: 50 kA
  • Standards: 250V and 600V Class H, K, and R - UL Listed Guide No. IZZR, CSA Certified. 600V Class J - UL Listed
  • Ul Certification: E105670 IZZR.E105670

Typical Applications

  • Industrial and Commercial Panelboards
  • Fuse Holder and Disconnect Retrofits
  • Power Distribution Equipment
  • Motor Control Centers
  • Electrical Switchgear Upgrades

Why Mersen?

Mersen fuse reducers are engineered to meet stringent UL and CSA safety standards, delivering dependable 600V-rated performance with a 50 kA SCCR for demanding electrical environments. Backed by rigorous certification testing under UL Guide No. IZZR and CSA 6225-01 207417, the Mersen 636 Fuse Reducer helps electrical professionals maintain code-compliant, reliable power distribution systems.

Manufacturer Resources

Mersen Product Catalog

Product Specs

Product Type:
Fuse Reducer
Voltage Rating:
600V
Listing:
UL Listed
Standards:
UL-CSA
Department:
Electrical
Product Group:
Circuit Protection
Product Subgroup:
Fuse Holders & Blocks

Mersen 636 – Frequently Asked Questions

1) What does a Mersen 636 fuse reducer actually do in a panel?
It adapts oversized fuse clips down to a smaller fuse size, so a disconnect or panelboard built for one amp-range fuse clip can accept a smaller Class H, K, or R fuse. Mersen's 636 handles that reduction between Class H, K, and R types, which is what makes it useful on fuse holder and disconnect retrofits where the switch is larger than the load needs.
2) Can I use the Mersen 636 reducer on a 600 volt disconnect?
Yes. The 636 is rated 600 VAC and 600 VDC, so it covers 600V switchgear, motor control centers, and distribution gear as well as lower-voltage 240V and 480V systems.
3) Is the Mersen 636 fuse reducer UL Listed and CSA certified for code work?
Both. It is UL Listed under Guide No. IZZR, certification E105670 IZZR.E105670, and CSA Certified under 6225-01 207417. It meets 250V and 600V Class H, K, and R UL requirements plus 600V Class J UL Listed standards, which is what an inspector or a spec-driven facility buyer will be looking for.
4) Will a Mersen 636 reducer work with Class R fuses, or only Class H and K?
Class R is covered. The 636 reduces between Class H, K, and R fuse types, and its standards compliance spans 250V and 600V Class H, K, and R. Note that reducers do not add rejection features, so if your switch needs Class R rejection to hold its listed interrupting rating, confirm the clip arrangement in the switch itself.
5) Will the Mersen 636 work in a Class J fused disconnect?
The Mersen 636 is built as a Class H and K fuse reducer and reduces between Class H, K, and R fuse types. Its standards coverage includes 250V and 600V Class H, K, and R under UL Guide No. IZZR with CSA certification, plus 600V Class J UL Listed standards. Class J clips use a different dimension and rejection profile than Class H/K, so verify the clip centers and blade dimensions of your Class J switch against the reducer you order rather than assuming a Class H/K body drops in. For an alternate source of the same clip-adapter function, the Littelfuse LRUR Series is the comparable line.
6) What short-circuit current rating does the Mersen 636 fuse reducer carry?
50 kA SCCR. That lets it stay in circuits where the available fault current at the panel runs high, which is the usual sticking point on an industrial retrofit.
7) What part number do I order for the Mersen Class H and K fuse reducer?
Order Mersen part 636. It is a single catalog number, not a family with options, so there is no finish, amp, or voltage selection to make on the order.
8) Where do fuse reducers like the Mersen 636 typically get installed?
Industrial and commercial panelboards, power distribution equipment, motor control centers, and switchgear upgrades. The common case is a disconnect retrofit: the switch was sized for a larger fuse than the circuit now needs, and the reducer lets the smaller fuse seat properly in the existing clips instead of replacing the switch.
9) What is the closest alternative to the Mersen 636 fuse reducer if I need a fuse clip adapter from another manufacturer?
The Littelfuse LRUR Series (also catalogued as the LRU2 Series) is a fuse reducer and fuse clip adapter that serves the same purpose of adapting fuse clips to a smaller fuse size. The Mersen 636 is a Class H and K fuse reducer rated 600 VAC and 600 VDC with a 50 kA SCCR, UL Listed under Guide No. IZZR, Certification E105670, and CSA Certified under 6225-01 207417. Confirm the voltage and amp-clip sizes of the LRUR part you select match the switch or panelboard clips you are adapting before ordering either.
10) I need to fit a smaller fuse into an existing 600V disconnect - do I buy a fuse reducer or a different fuse?
A fuse reducer is the right part when the switch clips are sized for a larger amp rating than the fuse you need to install. The Mersen 636 reduces between Class H, K, and R fuse types and is rated 600 VAC and 600 VDC with a 50 kA SCCR, so it lets a smaller-ampere fuse seat in larger clips without replacing the disconnect. If instead your clips already match your fuse ampere size and you only need different time-delay or interrupting characteristics, a different fuse is the answer and no adapter is needed. The Littelfuse LRUR Series is the comparable fuse clip adapter if you are sourcing the same function elsewhere.
11) Is the Mersen 636 RoHS compliant or lead free?
Mersen directs those two questions to their technical services rather than publishing a flat yes on the 636. If your facility is buying to a RoHS or lead-free procurement requirement, treat that as the item to verify before you standardize on it. What is confirmed on the part is UL Listing under Guide No. IZZR and CSA certification 6225-01 207417.
How fast can I get the Mersen 636 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 Mersen 636 come with a warranty?
Absolutely. The Mersen 636 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 Mersen 636?
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 Mersen 636 from ZenSupply?
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