MERSEN FUSE 12,5 URD 71 TT F 0400 12,5URD71TTF0400

High-speed fuse designed for semiconductor protection with 400A rating, 1250VAC IEC and 1300VAC UL voltage ratings, featuring flush ends with metric threads and integral striker indication.

SKU: D300521Alt SKU: PC71UD13C400TFMPN: D300521

List Price £154.30 ex VAT

Your Price (ex VAT)

£154.30

Manufacturer Lead Time Please contact us for a delivery time before you order

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Manufacturer Lead Time

£154.30

Why Choose the Mersen D300521 Industrial Electrical Component?

The Mersen D300521 is a genuine Mersen industrial electrical component intended for professional maintenance, repair and OEM replacement applications. It is identified by the manufacturer reference D300521 and should be selected where this exact part number is specified within the equipment documentation, approved bill of materials or existing installation.

A search of publicly available Mersen technical documentation did not identify a verified product record for the reference D300521. To avoid publishing inaccurate technical information, the electrical ratings, dimensions and operating characteristics have not been inferred from similar products. Always verify the manufacturer reference against the original component or official Mersen documentation before ordering or installation.

Using the correct manufacturer reference helps maintain equipment compatibility, supports reliable operation and reduces the risk of installing an unsuitable replacement component.

Key Advantages

Genuine Mersen manufacturer reference.
Supports accurate OEM replacement.
Suitable for professional maintenance applications.
Helps maintain equipment compatibility.
Ideal for preventative maintenance programmes.
Supports accurate procurement and inventory management.

Key Features

Manufacturer: Mersen.
Part number: D300521.
Industrial-grade replacement component.
Designed for compatible electrical equipment.
Suitable for OEM maintenance and repair.
Professional installation recommended.
Manufacturer identification clearly referenced.
Technical compatibility should always be verified before installation.

Selecting the Correct Replacement Component

Industrial electrical components that appear physically similar may have significantly different electrical ratings, mounting arrangements or operating characteristics. For this reason, replacement components should always be selected using the complete manufacturer reference together with the original equipment specification.

Where technical information is unavailable from verified manufacturer sources, the safest approach is to confirm the exact part number directly from the installed component or official Mersen technical documentation before purchase.

Typical Applications

Industrial electrical equipment.
OEM machinery.
Control panels.
Manufacturing systems.
Preventative maintenance.
Replacement of correctly specified Mersen components.

Technical Specifications

Item number	D300521
Catalogue No	PC71UD13C400TF
Description	Square Body High-Speed Fuse Protistor® Size 71 aR 1250VAC IEC 1300VAC UL 400A With Striker Flush ends metric threads
EAN/UPC Code	3605340329735
Rated voltage AC UL	1300 V
Rated voltage AC IEC	1250 V
Ampere Rating	400 A
AC or DC	AC
Speed/Characteristic	aR
Fuse Size	71
Mounting	Bolted
Clearing I2t At Rated Voltage	308 kA²s
Melting I2t	38 kA²s
AC Max I.R./Breaking Capacity	I1: 126 kA
Indication System	Yes
Indication System Type	Striker
Connection/Terminal Material	Silver-Plated Brass
Connection/Terminal Type	Flush ends
Product Width	51 mm
Product Length	74 mm
Product Height	56.5 mm
Sell Pack Quantity	3 EA
Sell Pack Weight	1.545 kg
Sell Pack Width	90 mm
Sell Pack Length	170 mm
Sell Pack Height	70 mm
Product group	Semiconductor Protection Fuses
Body/Insulating Material	Ceramic
Product Weight	0.515 kg
Power Dissipation at Rated Current Value	76 W
HS Code	85351000
Fuse Type	Semiconductor
Fuse Class	aR
Voltage	1250 V

Frequently Asked Questions

What is the Mersen D300521?

The Mersen D300521 is an industrial electrical component identified by the manufacturer part number D300521. Its detailed technical characteristics should be confirmed using official Mersen documentation.

Can I use a similar-looking replacement?

No. Components that appear identical may have different electrical ratings or operating characteristics. Always match the exact manufacturer reference.

Where can I verify compatibility?

Check the existing component label, equipment manual, approved bill of materials or official Mersen technical documentation.

Why are the electrical specifications not listed?

No verified public manufacturer information could be found for this exact part number, so specifications have not been estimated to avoid publishing inaccurate technical data.

Who should install this component?

Installation should be completed by a suitably qualified electrical engineer or technician following all applicable safety procedures.

Trusted Industrial Components from Mersen

Mersen products are specified worldwide by OEMs, panel builders and industrial maintenance professionals who require dependable replacement components for critical electrical equipment.

Item number	D300521
Catalogue No	PC71UD13C400TF
Description	Square Body High-Speed Fuse Protistor® Size 71 aR 1250VAC IEC 1300VAC UL 400A With Striker Flush ends metric threads
EAN/UPC Code	3605340329735
Rated voltage AC UL	1300 V
Rated voltage AC IEC	1250 V
Ampere Rating	400 A
AC or DC	AC
Speed/Characteristic	aR
Fuse Size	71
Mounting	Bolted
Clearing I2t At Rated Voltage	308 kA²s
Melting I2t	38 kA²s
AC Max I.R./Breaking Capacity	I1: 126 kA
Indication System	Yes
Indication System Type	Striker
Connection/Terminal Material	Silver-Plated Brass
Connection/Terminal Type	Flush ends
Product Width	51 mm
Product Length	74 mm
Product Height	56.5 mm
Sell Pack Quantity	3 EA
Sell Pack Weight	1.545 kg
Sell Pack Width	90 mm
Sell Pack Length	170 mm
Sell Pack Height	70 mm
Product group	Semiconductor Protection Fuses
Body/Insulating Material	Ceramic
Product Weight	0.515 kg
Power Dissipation at Rated Current Value	76 W
HS Code	85351000
Fuse Type	Semiconductor
Fuse Class	aR
Voltage	1250 V

UK delivery

Delivery options

Free UK delivery on orders over £200 ex VAT. Order in-stock items before 2pm Monday to Friday for next-day delivery.

This product Lead time on request

Please contact us for a delivery time before you order

Standard delivery

£8 ex VAT · free over £200

UK parcel delivery is £8 ex VAT, or free on orders over £200 ex VAT.

Heavier items may be charged at a weight-based or pallet rate, shown at checkout.

Collect from our showroom

Mon–Fri, 8am–5pm

Order and pay online, then collect from our showroom.

Please allow 15–30 minutes after ordering for us to prepare your order.

Northern Ireland, ROI & export

Priced at checkout

We deliver to Northern Ireland, the Republic of Ireland and overseas.

Delivery is calculated at checkout based on your destination.

Orders with mixed availability

Shipped complete

If part of your order is on a lead time, we hold it and send everything together.

Need the in-stock items sooner? Ask us and we can split the delivery.

Business customer returns

Returns & order support

Need to return an item? Find the guidance for your order below, then contact our team before sending anything back.

Stocked items

Request within 30 days

Changed your mind or ordered the wrong item? Request a return within 30 days of receipt. There is no restocking charge.

Items must be unused, in resalable condition and in their original packaging, and returns need our approval first. Return carriage is at your cost, and the original delivery charge is not refunded.

Faulty or damaged items

Tell us as soon as possible

Faulty, damaged on delivery or the wrong product supplied? Contact our team as soon as possible with the details.

We will review the issue and arrange an appropriate resolution under our terms and conditions and your statutory rights.

Made-to-order items

Manufacturer approval needed

Manufactured, configured and special-order products can only be returned with the manufacturer’s approval. Any handling charge is agreed with you when you request the return.

This does not affect claims for faulty goods or items that do not meet the agreed specification.

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Let’s get your return sorted.

Send your order number, product details and reason for return. For faults or delivery damage, include photographs if available. We will confirm the next steps.

Email returns team 01706 242050

The 30-day return request period applies to change-of-mind returns for stocked items. It does not limit your statutory rights for faulty or non-conforming goods.

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Credit Accounts

Our service agreements are built to support long term procurement relationships. By working closely with engineering teams and procurement departments, we help streamline purchasing processes while ensuring consistent access to critical components and sourcing support when it matters most.

Priority sourcing and supply support

Flexible payment terms for qualifying organisations

Support for engineering, maintenance, and operations

500 +

Stock lines ready to ship

1,000 +

Same day dispatches

3500 +

Customers supported

28 Trusted Manfacturers

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At Led Controls Ltd we help engineers source the right automation and control gear with confidence. below are quick answers to what we are asked most often.

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We supply all leading manfacturers in our industry. we offer next day delivery on most poplour products.

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