Mersen US6J3 UltraSafe Class J Fuse Holder, 60A 3-Pole DIN Rail, IP65
The Mersen US6J3 UltraSafe Class J Fuse Holder delivers reliable overcurrent protection for industrial and commercial applications requiring 600VAC/600VDC operation at 60A capacity. This 3-Pole unit mounts on standard DIN rail and combines a polyamide insulating body with an IP65 environmental rating, making it suitable for demanding indoor and outdoor panel installations. Clip-in Class J fuse installation and a 200 kA short circuit current rating round out a fuse holder built for panels where both protection and durability matter.
Key Features
- 600VAC/600VDC Dual Voltage Rating: Versatile operation across AC and DC applications with consistent 60A capacity for broad system compatibility.
- Class J Fuse Compatibility: Engineered for Class J fuses with clip-in installation method ensuring proper fit and reliable overcurrent protection.
- 200 kA Short Circuit Current Rating: High fault current interruption capability provides robust protection in demanding electrical environments.
- 3-Pole DIN Rail Mounting: Standard DIN rail installation enables quick panel integration with secure mechanical attachment.
- IP65 Environmental Protection: Sealed enclosure design protects against dust ingress and water jets for reliable outdoor and industrial operation.
- Durable Construction: Polyamide insulating material delivers excellent electrical insulation and mechanical strength.
- Flexible Wiring Range: Accommodates #2 to 14 AWG conductors with a 45 lb-in torque specification for secure terminations.
Certifications & Compliance
- RoHS Compliant
- IP65 Rated
- 200 kA Short Circuit Current Rating (SCCR)
Technical Specifications
- Rohs Compliant: Yes
Typical Applications
- Industrial Control Panels
- Commercial Electrical Distribution
- Motor Control Centers
- Power Distribution Equipment
- Manufacturing Facilities
- Renewable Energy Systems
Why Mersen?
Mersen UltraSafe fuse holders combine proven engineering with RoHS compliant construction and IP65 environmental protection. The robust polyamide insulating material and 200 kA short circuit current rating ensure reliable performance in demanding applications, while DIN rail mounting and a flexible #2 to 14 AWG wiring range simplify installation and maintenance for professional electrical work.
Manufacturer Resources
Mersen Product Catalog
Product Specs
- AC or DC:
- AC/DC
- Ampere Rating:
- 60 A
- Body/Insulating Material:
- Polyamide
- Frequency (Hz):
- 50/60 Hz
- Fuse Class:
- Class J
- Fuse Installation Method:
- Clip-in
- Fuse Type Class:
- Class J
- Installation Mounting:
- DIN Rail
- Max Fuse Rating:
- 60 A
- Number Of Poles:
- 3-Pole
- Product Height:
- 3.5 in
- Product Length:
- 4.8 in
- Product Weight:
- 1.83 lb
- Product Width:
- 4.72 in
- Rated voltage AC UL:
- 600 V
- Rated voltage DC UL:
- 600 V
- Rohs Compliant:
- Yes
- Short Circuit Current Rating Sccr:
- 200 kA
- Torque Rating:
- 45 lb-in
- Wiring Range:
- #2 to 14 AWG
- Department:
- Electrical
- Product Group:
- Circuit Protection
- Product Type:
- Fuse Holder
- Product Subgroup:
- Fuse Holders & Blocks
Mersen US6J3 – Frequently Asked Questions
1) What size and class of fuse does the Mersen US6J3 holder take?
The US6J3 takes Class J fuses up to 60 A, in a clip-in style holder. Class J bodies are dimensionally distinct from Class CC, T, or RK5, so only a Class J fuse in the 60 A case size will seat in it. It covers three poles in one block.
2) Can I use this Mersen fuse holder on a DC solar or battery circuit, not just AC?
Yes. The US6J3 is rated 600 V AC and 600 V DC, at 60 A, with AC operation at 50/60 Hz. That dual rating is why it shows up in PV and energy-storage panels as well as standard motor control gear.
3) What wire size and torque do the terminals on the US6J3 take?
Terminals accept #2 through 14 AWG and land at 45 lb-in. That range covers a 60 A feeder in copper as well as much smaller control conductors, so one block works for both branch and control work. Use a torque screwdriver or wrench rather than feel, since loose Class J clips are a common source of nuisance heating.
4) Will the Mersen US6J3 fit in my enclosure and on standard DIN rail?
It mounts on standard DIN rail and measures 4.8 x 4.72 x 3.5 inches, weighing 1.83 lb. Check that depth against your panel door clearance before you lay out the rail, because a three-pole Class J block is considerably deeper than a typical breaker.
5) Does this fuse holder support a 200 kA SCCR panel rating?
The US6J3 carries a 200 kA short circuit current rating, which is why it is specified in industrial control panels where the assembly SCCR has to be documented. The Class J fuse installed in it is the current-limiting element that makes that rating usable.
6) Is the Mersen US6J3 OK in a washdown or outdoor panel?
It is rated IP65, so dust-tight and protected against water jets, with a polyamide insulating body. That suits wet or dusty plant areas and outdoor enclosures. The fuses themselves are not included, so order three Class J fuses sized to the load separately.
7) I need a fuse holder for a low-voltage or in-line run, not a 600 V panel block. What should I look at instead?
The Mersen US6J3 is a 600 V, 60 A panel-mount Class J block and it is wrong for small in-line work. For a watertight in-line holder on a cable run, look at the Littelfuse WPB1 Series. For a 125 V, 15 A plug fuse box cover application, the Littelfuse LSRY Series is the fitting type.
8) Can I use the Mersen US6J3 on a single-phase or two-wire circuit?
It is a fixed 3-pole block, so all three poles come as one unit on the rail. You can leave a pole unused on a single-phase feed, but you are paying for and mounting three positions. If the panel only needs one or two poles, specify the matching 1- or 2-pole UltraSafe Class J holder in the 60 A frame instead.
9) Can I use a Littelfuse LSRY plug fuse box cover unit instead of the Mersen US6J3?
Only if the circuit is a low-voltage, low-current one. The Littelfuse LSRY series is a plug fuse box cover unit rated 125 V and 15 A, which is a residential-style plug fuse format. The Mersen US6J3 accepts clip-in Class J fuses up to 60 A and is rated 600 V AC and 600 V DC with a 200 kA short circuit current rating, which is what industrial control panels and motor control circuits are typically specified around. The two are not interchangeable on the same circuit.
10) For a wet or washdown location, which fuse holder is the better choice?
It depends on whether the fuses live inside an enclosure or out on the cable. The Mersen US6J3 uses a sealed polyamide body and is built for DIN rail mounting in panels exposed to dust and water jets, and it handles all three poles in one unit. The Littelfuse WPB1 is a watertight in-line holder, so it protects a single fuse spliced directly into a cable run with no panel required. Choose the US6J3 when the protection lives in a panel and you need three poles; choose an in-line watertight holder when there is no enclosure to mount to.
11) Is the US6J3 RoHS compliant for a spec that requires it?
Yes, it is listed RoHS compliant, which is usually the gate on institutional and export panel builds. The polyamide body and clip-in Class J construction are unchanged by that.
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Does the Mersen US6J3 come with a warranty?
Absolutely. The Mersen US6J3 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
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