Mersen OTS-15 Amp-Trap Class K...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$27.66
Mersen OTS-15 Amp-Trap Class K5 Fast-Acting Fuse, 600VAC/300VDC

Mersen OTS-15 Amp-Trap Class K5 Fast-Acting Fuse, 600VAC/300VDC

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Model: OTS15

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

$27.66
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Mersen OTS-15 Amp-Trap® Class K5 Fast-Acting Fuse, 600VAC/300VDC

The Mersen OTS-15 Amp-Trap® is a Class K5, fast-acting One-Time (OTS) general purpose fuse engineered for low-cost, reliable protection of feeder and branch-circuits serving lighting, heating, and other non-motor loads. Rated 600VAC and 300VDC with an AC Max Interrupting Rating of 50 kA, this fuse safely interrupts available short-circuit currents up to 50,000 amperes. This listing covers the OTS-15 family, available with a choice of Blade or Ferrule connection to match your specific fuse holder or disconnect configuration — select the connection type needed at checkout. Note that OTS fuses are not rejection-style fuses, so any replacement fuse should never carry a lower interrupting rating than the original unit being replaced.

Key Features

  • Fuse Class: Class K5 construction for general-purpose branch and feeder-circuit protection.
  • Speed/Characteristic: Fast-Acting response provides rapid interruption of overcurrent conditions to protect downstream equipment and conductors.
  • Dual AC/DC Rating: Rated 600V AC and 300V DC (UL), giving flexibility for use across both AC and DC circuit applications.
  • Interrupting Capacity: 50 kA AC Max I.R./Breaking Capacity delivers safe interruption of high short-circuit currents within its rating range.
  • Connection Options: Available in Blade or Ferrule terminations to fit standard fuse holder and disconnect hardware — choose the connection style that matches your equipment.
  • Frequency: Rated for 50/60 Hz electrical systems, suitable for standard commercial and industrial power frequencies.
  • Packaging: Supplied 10 EA per package, convenient for maintenance stock or multi-fuse panel installations.

Certifications & Compliance

  • RoHS Compliant

Technical Specifications

  • ROHS Compliant: Yes
  • Fuse Class: Class K5
  • Speed/Characteristic: Fast-Acting
  • Rated Voltage AC (UL): 600V
  • Rated Voltage DC (UL): 300V
  • AC Max I.R./Breaking Capacity: 50 kA
  • Connection Type: Blade or Ferrule (select at checkout)
  • Frequency: 50/60 Hz

Typical Applications

  • Feeder and Branch-Circuit Overcurrent Protection
  • Lighting and Heating Circuit Protection
  • Non-Motor Load Circuits
  • Commercial and Industrial Electrical Panels
  • Fuse Replacement and Maintenance Stock
  • AC and DC Circuit Applications up to 600VAC/300VDC

Why Mersen?

Mersen's OTS-15 Amp-Trap® Class K5 fuses combine fast-acting protection with a 50 kA interrupting rating and dual 600VAC/300VDC ratings, giving electrical professionals dependable, code-compliant overcurrent protection for general-purpose feeder and branch-circuit applications. Offered in Blade or Ferrule connection styles, the OTS-15 series adapts to a wide range of fuse holders and disconnect hardware while maintaining consistent, repeatable performance. The RoHS-compliant construction further supports responsible sourcing for panel and disconnect installations. Always match replacement fuse interrupting ratings to the original device to maintain system protection integrity.

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Manufacturer Resources

Mersen Product Catalog

Product Specs

Mounting Method:
Clip
AC Max I.R./Breaking Capacity: I1:
50 kA
ROHS Compliant:
Yes
Frequency (Hz):
50/60 Hz
Rated voltage AC UL:
600 V
Speed/Characteristic:
Fast-Acting
AC or DC:
AC/DC
Rated voltage DC UL:
300 V
Fuse Class:
Class K5
list_batch:
MERSEN-20260825
Department:
Electrical
Product Group:
Circuit Protection
Product Type:
Fast-Acting Fuse
Voltage Rating:
600V
Listing:
RoHS Compliant
Amperage Rating:
50kA AC Max I.R.
Configuration:
Blade or Ferrule
Grade:
Class K5
Product Subgroup:
Fuses

Mersen OTS15 – Frequently Asked Questions

1) Can the Mersen OTS-15 fuse be used on a 300V DC circuit as well as 600V AC?
Yes. The OTS-15 Amp-Trap carries dual UL ratings: 600V AC and 300V DC, so the same fuse covers both AC panel work and DC circuits up to 300 volts. On the AC side it is rated 50/60 Hz, which covers standard commercial and industrial power. Do not apply it above either voltage figure.
2) Do I order the blade or the ferrule version of the Mersen OTS-15?
That is decided by the fuse holder or disconnect you are fitting into, not by the circuit. The OTS-15 is offered in two terminations: ferrule, ordered as OTS15, and blade (knife-blade), ordered as OTS100. Both mount in clips. Pull the old fuse and look at the ends: smooth cylindrical caps mean ferrule, flat metal tabs mean blade. They are not interchangeable in the same clip set.
3) Is a Class K5 fuse a legal replacement for the Class K5 fuses in my existing disconnect?
Class K5 to Class K5 is the straight swap, and the OTS-15 is Class K5 with a 50 kA AC interrupting rating. The thing to watch: OTS fuses are non-rejection, meaning they will physically drop into holders built for other classes. Because nothing stops the wrong fuse going in, never install a replacement with a lower interrupting rating than the unit coming out, or you lose the short-circuit protection the panel was designed around.
4) Will a fast-acting OTS fuse hold on a motor circuit, or do I need time-delay?
Fast-acting is the wrong characteristic for motor starting. The OTS-15 is a fast-acting, general-purpose one-time fuse intended for feeder and branch circuits feeding lighting, heating and other non-motor loads, and motor inrush will nuisance-open it. For motor branch circuits, use a time-delay fuse instead, such as the Littelfuse CCMR Series Class CC time-delay fuse (CCMR040 in 40A).
5) Is 50 kA enough interrupting rating for my service?
The OTS-15 will safely clear available short-circuit current up to 50,000 amperes AC. If your fault-current study at that panel shows less than 50 kA available, you are covered. If the study shows more, or if the fuse being replaced was rated above 50 kA, this is not the right fuse for that location.
6) Can a Littelfuse CCMR040 Class CC fuse be used in place of a Mersen OTS-15 Class K5 fuse?
No. The Mersen OTS-15 Amp-Trap is a Class K5 fast-acting fuse rated 600VAC and 300VDC with a 50 kA AC interrupting rating, and it mounts in clips sized for its blade or ferrule termination. The Littelfuse CCMR040 is a Class CC time-delay fuse in the CCMR series, a different class with a different body size, a rejection-style mounting, and a time-delay curve rather than fast-acting. The two are not interchangeable in the same holder or disconnect, and Mersen notes that any OTS replacement should never carry a lower interrupting rating than the unit being replaced.
7) My metering circuit needs small 600V fuses - does the Mersen OTS-15 cover that, or is there a better choice?
The Mersen OTS-15 Amp-Trap is a general-purpose Class K5 fuse for feeder and branch circuits feeding lighting, heating, and other non-motor loads at 600VAC/300VDC, and it ships 10 each per package as maintenance stock. For instrument and metering duty, the Square D PowerLogic energy meter fuse pack is a set of three 0.5A 600V fuses supplied specifically for PowerLogic energy meters. Choose by what the circuit protects: panel feeders and branches versus a meter input.
8) Is the OTS-15 a renewable fuse or does it get thrown away after it blows?
One-time only. OTS stands for one-time, so once the element opens the fuse is scrap and gets replaced, not re-linked. That is why it ships 10 per package, which suits MRO shelf stock or loading several holders in a panel at once.
9) Are Mersen OTS fuses RoHS compliant for a spec that requires it?
Yes, the OTS-15 Amp-Trap is RoHS compliant, which covers the restricted-substances line item on most institutional and government electrical submittals.
How fast can I get the Mersen OTS15 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 OTS15 come with a warranty?
Absolutely. The Mersen OTS15 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 OTS15?
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 OTS15 from ZenSupply?
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