MERSEN FUSE MB4a 1250A 3P 1.000.090 1.000.090

Robust 1×3-pole fuse-switch disconnector with bottom fitting/panel connection and Screw M16 terminals, rated at 1250A for industrial electrical distribution.

SKU: W1023082Alt SKU: 1.000.090MPN: W1023082

List Price £1,772.33 ex VAT

Your Price (ex VAT)

£1,772.33

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

Get the best trade prices Trade exclusive

Create a trade account to unlock exclusive pricing, special offers and more.

Quantity:

SUBTOTAL (EX VAT) £1,772.33

Trade pricing is personalised to your account

Manufacturer Lead Time

£1,772.33

Why Choose the NH Fuse-Switch Disconnector MULTIBLOC® Size 4a 1250A?

The NH fuse-switch disconnector MULTIBLOC® Size 4a 1250A offers robust and reliable 1x3-pole switching for high-capacity electrical distribution and industrial power systems. Engineered for demanding applications, it ensures secure bottom fitting/panel connection with strong Screw M16 terminals, supporting efficient installation and long-term service.

This unit is designed to facilitate safe and rapid fuse changes while maintaining maximum electrical safety and operational continuity. Its durable construction and precise switching capabilities make it ideal for critical load protection and isolation in modern electrical infrastructures.

Product Code: W1023082

Key Benefits

High current rating of 1250 A suitable for heavy-duty industrial applications.
Reliable 1x3-pole switching ensures comprehensive circuit isolation.
Robust bottom fitting/panel connection with Screw M16 terminals for secure installation.
Designed for safe and quick fuse replacement to minimise downtime.
Complies with RoHS standards, ensuring environmental safety.
Durable construction with high rated impulse withstand voltage (8 kV) and short circuit withstand capacity (50 kA).

Compatibility

This fuse-switch disconnector is compatible with NH fuse size 4a and designed for use in IEC fuse switch disconnector systems. It supports both AC and DC utilization categories when used with solid links, making it suitable for integration into a wide range of industrial electrical distribution setups.

Applications

Industrial power distribution panels requiring high-capacity circuit protection.
Electrical installations needing secure and rapid fuse switching and isolation.
Critical load protection in manufacturing plants and heavy machinery.
Renewable energy systems requiring reliable disconnection and protection.
Infrastructure projects with demanding electrical safety and operational continuity requirements.

Technical Specifications

Current	4 A
Phase	Three Phase
Item number	W1023082
Catalogue No	1.000.090
Description	NH fuse-switch disconnector MULTIBLOC® Size 4a 1250A 1x3-Pole switching Bottom Fitting/panel Connection Screw M16
EAN/UPC Code	4027597028756
Frequency (Hz)	50 ... 60 Hz
Rated voltage AC IEC	400 V
Ampere Rating	1250 A
Utilization Category	AC 22 B @ Ue = AC 400 V; Ie = 1250 A DC 20 B @ Ue = DC 1000 V; Ie = 1250 A (with solid links)
Switchability	1x3-pole switching
RoHS Compliant	Yes
AC or DC	AC
Fuse Size	4a
Design Details	triple pole switching
Number of Poles	3-Pole
Degree of Pollution	3
Rated Impulse Withstand Voltage	8 kV
Rated Insulation Voltage	800 V
Rated SC Withstand	50 kA / 1 s
Max Power dissipation of Fuse Links Pn	115 W
Max Power dissipation of Solid Links Pn	42 W
Power Dissipation by Ith without Fuse-Links	180 W
Power Dissipation by Ith without Solid Links	180 W
Rated short circuit making capacity with solid links Icm	100 kA
Installation Mounting	Bottom Fitting/panel
Product Width	378 mm
Product Length	233 mm
Product Height	330 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	12.5 kg
Sell Pack Width	410 mm
Sell Pack Length	415 mm
Sell Pack Height	270 mm
Product group	IEC Fuse Switch Disconnectors
Conventional Free Air thermal Current With Fuse-Links Ith	1250 A
Product Weight	12.5 kg
Conventional Free Air thermal Current - Solid Links	1500 A
HS Code	85365080
Country of Manufacture	Hungary
Poles	3-pole
Device Type	Fuse switch disconnector
Voltage	400 V

Frequently Asked Questions

What is the maximum current rating of this fuse-switch disconnector?

The maximum ampere rating is 1250 A, suitable for high-capacity industrial applications.

Can this device be used for DC applications?

Yes, it supports DC 20 B utilisation category at DC 1000 V and 1250 A when used with solid links.

What type of mounting does this product use?

The fuse-switch disconnector is designed for bottom fitting or panel mounting.

Is this product RoHS compliant?

Yes, it complies with RoHS standards ensuring it meets environmental safety requirements.

Common Search Terms

NH fuse switch disconnector, MULTIBLOC Size 4a, 1250 amp fuse switch, 3-pole fuse switch, IEC fuse switch disconnector, industrial fuse switch, bottom fitting fuse switch, screw M16 terminal fuse switch, high current fuse switch, electrical distribution fuse switch.

Current	4 A
Phase	Three Phase
Item number	W1023082
Catalogue No	1.000.090
Description	NH fuse-switch disconnector MULTIBLOC® Size 4a 1250A 1x3-Pole switching Bottom Fitting/panel Connection Screw M16
EAN/UPC Code	4027597028756
Frequency (Hz)	50 ... 60 Hz
Rated voltage AC IEC	400 V
Ampere Rating	1250 A
Utilization Category	AC 22 B @ Ue = AC 400 V; Ie = 1250 A DC 20 B @ Ue = DC 1000 V; Ie = 1250 A (with solid links)
Switchability	1x3-pole switching
RoHS Compliant	Yes
AC or DC	AC
Fuse Size	4a
Design Details	triple pole switching
Number of Poles	3-Pole
Degree of Pollution	3
Rated Impulse Withstand Voltage	8 kV
Rated Insulation Voltage	800 V
Rated SC Withstand	50 kA / 1 s
Max Power dissipation of Fuse Links Pn	115 W
Max Power dissipation of Solid Links Pn	42 W
Power Dissipation by Ith without Fuse-Links	180 W
Power Dissipation by Ith without Solid Links	180 W
Rated short circuit making capacity with solid links Icm	100 kA
Installation Mounting	Bottom Fitting/panel
Product Width	378 mm
Product Length	233 mm
Product Height	330 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	12.5 kg
Sell Pack Width	410 mm
Sell Pack Length	415 mm
Sell Pack Height	270 mm
Product group	IEC Fuse Switch Disconnectors
Conventional Free Air thermal Current With Fuse-Links Ith	1250 A
Product Weight	12.5 kg
Conventional Free Air thermal Current - Solid Links	1500 A
HS Code	85365080
Country of Manufacture	Hungary
Poles	3-pole
Device Type	Fuse switch disconnector
Voltage	400 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.

LED Controls showroom with electrical products on display

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.

● Service Agreements

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

● frequently asked questions

Common questions about our products and support

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.

What product ranges do you supply

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

Can you help specify the correct part?

Your content goes here. Edit or remove this text inline or in the module Content settings. You can also style every aspect of this content in the module Design settings and even apply custom CSS to this text in the module Advanced settings.

Do you have stock for urgent orders?

What are your delivery times and costs?

What about warranties, returns and faulty items?

● latest blog

Discover our latest insights and
expert advice

From a Simple Idea to Small Business of the Year: The LED Controls Story So Far…

by admin | Aug 11, 2026 | News

LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.

LED Controls: Danfoss Drives Authorised Partner

by admin | Jan 17, 2026 | Product Spotlight

2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...

LED Controls: Your Complete Control Panel Solution