Mersen Fuses, Fuse Holders and Surge Protection
ATEK Distribution is a service-disabled veteran-owned electrical distributor and a Mersen supply partner. We quote and source Mersen fuses, fuse holders and blocks, surge protective devices, DC fuses and low-voltage disconnects for contractors, facilities, OEMs and public-sector buyers nationwide.
Send a part number, a photograph of the existing fuse, or the line item off your drawing. You get availability, lead time and price back within one business day — often the same day. If the part is obsolete or the class is wrong for the application, we will say so and give you the current equivalent.
Mersen product families we source
Mersen's North American electrical protection range covers low-voltage industrial fuses through to surge protection and DC distribution. The families below are the ones buyers ask us for most often.
| Family | What it is | Typical application |
|---|---|---|
| Amp-Trap 2000® | Mersen's main low-voltage industrial fuse line, spanning the UL 248 classes | Feeders, branch circuits, motor and transformer protection |
| A6D series (Class RK1) | Current-limiting Class R fuses with low let-through energy | Upgrading existing Class H, K or RK5 installations at 600 A and below; Type 2 starter coordination; arc-flash reduction |
| TRS…R series (Class RK5) | General-purpose dual-element time-delay Class R fuses | Feeder and branch protection where no component damage limit applies |
| A4J series (Class J) | Fast-acting Class J fuses, 600 V AC / 300 V DC | Compact panel designs, control circuits, equipment protection |
| Reducer Fuse Series | Class RK1 and Class J fuses that let a smaller fuse be fitted to a larger-rated holder | Downsizing protection without changing the switch or block |
| UltraSafe™ and Modulostar® holders | Finger-safe Class CC and Class J fuse holders (CUS10, CUSCC) | DIN-rail control panels, machine builds |
| Class J Fuse Holders — Gen2 | Current-generation Class J holder platform | New panel designs and holder replacement |
| Compact Fused Switches | Combined switch and Class CC or Class J fuse carrier | Space-constrained disconnect and protection in one device |
| Low-voltage disconnect switches | Fusible and non-fusible LV disconnects | Service and equipment disconnecting means |
| Compact power distribution blocks | Finger-safe distribution blocks | Panel power distribution and tap connections |
| Surge-Trap® SPDs | Pluggable series and NEMA UL/CSA Type 1 series surge protective devices, built on TPMOV® technology | Service entrance and panel-level surge protection |
| MDC and DQS DC fuses | DC distribution fuses and fast-acting DC fuses | Solar, energy storage, EV charging and DC drive systems |
Need something not listed — semiconductor and high-speed fuses, cooling, bus bar, or a Mersen catalogue number you already have? Send us the number and we will confirm what is available and how quickly.
What we can help you work out
Cross-referencing an obsolete or competitor part
Most fuse enquiries we see start with a photograph of a blown fuse and a part number that no longer exists. Send what you have — catalogue number, voltage and ampere markings, class, and the holder it came out of — and we will identify the current Mersen equivalent, or tell you plainly if there isn't one.
Upgrading away from Class H and RK5
If you are replacing fuses in older gear, the replacement decision is also a protection decision. Class H fuses are not current-limiting, and a fuse with no marked interrupting rating is a 10,000 A device under NEC 240.60 — a figure modern services routinely exceed. Mersen's A6D Class RK1 fuses fit the same holders as Class H, K and RK5 fuses at 600 A and below, so the upgrade usually needs no hardware change.
The trade-offs, the UL 248 let-through limits and the selectivity check you should run first are set out in our guide to RK1 vs RK5 fuses.
Specifying from scratch
Tell us the voltage, the load, what the fuse is protecting and the available fault current at that point, and we will quote against the class the application actually needs rather than the one that happens to be cheapest. Our industrial fuse selection guide covers the same ground if you would rather specify it yourself first.
Who we supply
- Electrical contractors — project quantities, job-site delivery, documentation for inspection.
- Facilities and maintenance teams — MRO replenishment, cross-references for legacy gear, emergency replacements.
- OEMs and panel builders — holders, blocks and fuses to a bill of materials.
- Government and institutional buyers — ATEK is a GSA contract holder and holds SDVOSB certification (CVE/SBA and SBA VetCert), NVBDC service-disabled veteran-owned certification, Disability:IN DOBE certification, Minnesota Targeted Group Business / SDVOSB status, and CERT Small Business Enterprise status in Hennepin County, Ramsey County and the City of Saint Paul. See government and public-sector purchasing.
Why buyers route Mersen enquiries through us
- Nationwide sourcing. We are not limited to one branch's shelf; we source across manufacturers and locations to fill a BOM.
- Technical answers, not just a price. If the class is wrong for the load, you hear about it before you buy.
- One supplier across categories. Fuses alongside circuit breakers, conduit and cable support, boxes and enclosures and wire and cable on one quote and one delivery.
- Documentation support for compliance and inspection.
- 24/7 emergency service when a line is down.
Request a quote
Send any of the following and we will work from it: a Mersen part number, a photo of the fuse and holder, a drawing line item, a spreadsheet BOM, or just a description of what failed and what it was protecting.
Frequently asked questions
Is ATEK Distribution a Mersen distributor?
ATEK Distribution is an electrical distributor based in Minneapolis, Minnesota, serving customers nationwide, and Mersen is one of our manufacturer supply partners. We quote, source and supply Mersen electrical protection products — fuses, holders and blocks, surge protective devices, DC fuses and low-voltage disconnects. Send a part number and we will confirm availability, lead time and price.
Which Mersen fuse classes can you supply?
Mersen's low-voltage industrial range covers the UL 248 classes used in North American commercial and industrial gear — Class R (RK1 and RK5), J, CC, T and L among them — plus DC fuse families for solar, storage and EV charging. Send the class and rating you need and we will confirm availability.
Can you cross-reference a fuse from another manufacturer?
ATEK can cross-reference a fuse from another manufacturer to a Mersen equivalent. Send the existing part number along with the voltage, ampere rating and class markings, and a photo of the holder if you have one. Class, voltage, ampere rating and interrupting rating all have to match — a fuse that physically fits is not automatically a correct replacement.
Do you supply Mersen surge protective devices?
ATEK supplies Mersen surge protective devices, including the Surge-Trap® pluggable series and the NEMA UL/CSA Type 1 series, both built on Mersen's TPMOV® technology. Tell us the system voltage, configuration and where in the distribution system the SPD is going.
How fast can I get a quote?
You can expect a quote within one business day, and often the same day. For a line-down emergency, say so in the request and use our 24/7 emergency service.
Can you supply Mersen on a GSA or SDVOSB set-aside order?
ATEK can supply Mersen on a GSA or SDVOSB set-aside order. ATEK Distribution is a GSA contract holder and an SDVOSB-certified source. See government purchasing for contract vehicles, certifications and NAICS registrations.
Related pages
- RK1 vs RK5 fuses — the upgrade decision, with UL 248 let-through limits.
- Industrial fuse selection guide — how to specify voltage, ampere, interrupting rating and class.
- Types of fuses — fuse families explained.
- Molded case circuit breakers — the breaker side of circuit protection.
- Power and protection products — the full category.
Send a Mersen part number, a photo of the fuse and holder, or your BOM. ATEK Distribution is a Minneapolis, Minnesota electrical distributor supplying nationwide, and a Mersen supply partner. Quote responses go out within one business day, often the same day.