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Mersen A6T60 Class T Fast-Acting Fuse, 60A 600VAC/300VDC Ferrule
Model: MER-A6T60
Mersen A6T60 Class T Fast-Acting Fuse, 60A 600VAC/300VDC FerruleThe Mersen A6T60 Class T Fast-Acting Fuse delivers reliable overcurrent protection rated 60A for both 600VAC and 300VDC applications...
Mersen
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Mersen A6T40 Class T Fast-Acting Fuse, 40A 600VAC/300VDC
The Mersen A6T40 Class T Fast-Acting Fuse (Amp-Trap) delivers professional-grade circuit protection with a 40A current rating and dual voltage capability of 600VAC/300VDC. Built with a GMG insulating body and copper ferrule terminals, this fast-acting fuse offers a 200 kA breaking capacity for demanding commercial and industrial electrical applications, with a rated frequency of 50/60 Hz.
Key Features
- 40A Current Rating: Provides precise overcurrent protection for medium-duty electrical circuits and equipment.
- Dual Voltage Rating: Rated 600VAC/300VDC for versatile compatibility across AC and DC applications in commercial and industrial settings.
- Class T Fast-Acting Response: Rapid fault clearing minimizes equipment damage and enhances system safety during overcurrent conditions.
- 200 kA Breaking Capacity: High interrupting rating (AC max I'R breaking capacity) handles severe fault currents in high-energy electrical systems.
- Ferrule Terminal Design: Copper ferrule terminals ensure secure connections and reliable electrical contact in compatible fuse holders.
- GMG Body Construction: Professional insulating material provides durability and electrical isolation in demanding environments.
- Clip Mounting Method: Simple installation and replacement in compatible fuse holders and electrical panels.
- Compact Footprint: Product length of 1.57 in and weight of 0.083 lb suit space-constrained panel and enclosure layouts.
Technical Specifications
- Body Insulating Material: GMG
- Ampere Rating: 40 A
- Rated Voltage AC UL: 600 V
- Rated Voltage DC UL: 300 V
- Fuse Class: Class T
- Speed Characteristic: Fast-Acting
- AC Max I'R Breaking Capacity I1: 200 kA
- Connection Terminal Type: Ferrule
- Connection Terminal Material: Copper
- Mounting Method: Clip
- Frequency: 50/60 Hz
- Product Length: 1.57 in
- Product Weight: 0.083 lb
Typical Applications
- Commercial Building Electrical Panels
- Industrial Motor Control Centers
- HVAC Equipment Protection
- Lighting Control Systems
- Power Distribution Equipment
- Electronic Equipment Protection
- Emergency Power Systems
Why Mersen?
Mersen fuses deliver proven reliability with professional-grade construction and precise overcurrent protection. The Class T fast-acting design, 200 kA breaking capacity, and copper ferrule terminals ensure dependable performance in critical electrical applications, backed by Mersen's commitment to electrical safety and system protection.
Manufacturer Resources
Mersen Product Catalog
Product Specs
- Product Type:
- Fast-Acting Fuse
- Product Material:
- GMG
- Amperage Rating:
- 40A
- Voltage Rating:
- 600VAC/300VDC
- Connection Type:
- Ferrule
- Department:
- Electrical
- Product Group:
- Circuit Protection
- Product Subgroup:
- Fuses
- Product Weight:
- 0.083 lb
- Product Length:
- 1.57 in
Mersen A6T40 – Frequently Asked Questions
1) Will a Mersen A6T40 fuse fit a Class T fuse holder or block?
Yes, as long as the holder is Class T rated for 600V and 40A. The A6T40 is a 600VAC Class T fuse with copper ferrule terminals and a clip mounting style, so it drops into 600V Class T clips. Class T bodies are dimensionally unique by class and voltage rating, so a 300V Class T block will not take it and neither will a Class J or Class CC holder.
2) Can I use the Mersen A6T40 on a 300V DC circuit like a battery or solar string?
Yes. The A6T40 carries a dual rating of 600VAC and 300VDC, so it can be applied on DC circuits up to 300 volts. Above 300VDC you need a different device. On AC it is rated for 50/60 Hz systems.
3) Should I use a Class T fast-acting fuse or a Class CC time-delay fuse for a motor circuit?
They do different jobs. The Mersen A6T40 is fast-acting, so it clears faults quickly to limit let-through energy, which suits transformers, panelboards, meters, and electronic equipment but will nuisance-open on motor inrush. For a motor branch circuit you want a time-delay fuse that rides through starting current, such as the Littelfuse CCMR040 Class CC time-delay fuse at the same 40A. Note the two are not interchangeable in the holder, since Class CC and Class T use different mounting dimensions.
4) What is the difference between the Mersen A6T40 and the Littelfuse CCMR040 for a 40A branch circuit?
Both are 40A fuses, but they are different classes with different response curves. The Mersen A6T40 is a Class T fast-acting fuse rated 600VAC/300VDC, built to clear faults quickly. The Littelfuse CCMR040 is a Class CC time-delay fuse, designed to ride through the inrush of a motor start before clearing. If the load is a motor and you need the fuse to tolerate starting current, the CCMR040 is the time-delay option; for fast fault clearing on feeders and equipment protection, the A6T40 is the fast-acting choice. They also use different holders, so the two are not interchangeable in the same block.
5) My 40A fuse keeps opening on motor startup - what should I use instead of the Mersen A6T40?
A fast-acting fuse is doing exactly what it is built to do on a motor inrush. The Mersen A6T40 is a Class T fast-acting fuse, so it clears quickly on any current spike, including a legitimate start. For motor branch circuits, the Littelfuse CCMR040 is a 40A Class CC time-delay fuse that tolerates starting current. Confirm the holder is Class CC rejection style before ordering, since it will not accept a Class T ferrule body.
6) Is 200 kA interrupting rating enough for my service entrance or MCC?
The A6T40 interrupts up to 200 kA at its AC rating, which is the highest available fault current rating commonly specified and covers service entrances, motor control centers, and other high energy distribution where available fault current runs high. Match it to the available fault current calculated for your service.
7) Why choose a Class T fuse instead of a standard glass tube or midget fuse?
Size and fault capability. The Class T A6T40 is a 600V, 200 kA current-limiting fuse for power distribution, roughly 1.57 inches long, so it protects switchgear and feeders. Glass tube and midget fuses are control and low-energy devices by comparison: the Littelfuse BLF Series midget is a 250V fast-acting fuse, and the AGA and AGU series are glass tube fuses. Those belong in control circuits, meters, and accessory loads, not on a 600V feeder.
8) Is the Mersen A6T40 the same thing as an Amp-Trap A6T40?
Yes. Amp-Trap is Mersen's brand name for this Class T line, and the part number to order is A6T40: a 40A, 600VAC/300VDC Class T fast-acting fuse. The A6T prefix denotes the 600V Class T family, with the trailing number giving the amp rating.
9) Is a Littelfuse AGU or AGA glass fuse an alternative to the Mersen A6T40?
They serve entirely different duty. The Littelfuse AGU and AGA series are small glass tube fuses - the AGA5 is a 5A glass fuse - used for electronics, accessory, and low-current circuits. The Mersen A6T40 is a 40A Class T fuse with a GMG insulating body, copper ferrule terminals, and a 200 kA breaking capacity for commercial and industrial panel work. Glass tube fuses are not a substitute where a high interrupting rating is required.
10) For metering circuits, should I order the Mersen A6T40 or the Square D PowerLogic fuse pack?
Use the Square D PowerLogic Energy Meter Fuse Pack for the meter itself - it is a set of three 0.5A 600V fuses sized for metering potential circuits. The Mersen A6T40 is a 40A Class T fuse intended for the power circuit it protects, not the meter's voltage-sensing leads. On a switchgear job you may well need both: the A6T40 on the load side protection and the PowerLogic pack behind the meter.
11) What is the Mersen A6T40 made of and will it hold up in a hot industrial panel?
The body is GMG insulating material with copper ferrule end terminals. Copper ferrules give a low-resistance contact in the clips, which matters in a tightly packed enclosure where heat rise from a poor connection is the usual failure. Clean the clips and check clip tension when you replace it.
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Does the Mersen A6T40 come with a warranty?
Absolutely. The Mersen A6T40 is backed by a manufacturer’s warranty.
For full warranty terms, check the product documentation or Contact Us.
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