MERSEN FUSE MB1 250A 3PTRI40/60 1.000.323 1.000.323

NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10, designed for reliable protection and efficient operation within industrial switchgear assemblies.

SKU: T229879Alt SKU: 1.000.323MPN: T229879

List Price £320.27 ex VAT

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£320.27

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Manufacturer Lead Time

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Why Choose the NH Fuse-Switch Disconnector MULTIBLOC® Size 1 250A 3-Pole?

Engineered for reliable protection and efficient operation within 40mm bus bar systems, this NH fuse-switch disconnector delivers proven performance at up to 250A across three poles. The robust screw M10 terminals ensure secure, low-resistance connections and facilitate straightforward installation in industrial switchgear assemblies.

Certified for demanding environments, the MULTIBLOC® design supports safe electrical isolation and simplifies maintenance procedures. Depend on this solution for high integrity circuit protection and long-term operational safety in your power distribution applications.

Product Code: T229879

Key Benefits

Reliable circuit protection up to 250A with 3-pole switching capability.
Robust screw M10 terminals for secure and low-resistance connections.
Compatible with 40 mm and 60 mm bus bar systems for flexible installation.
High short circuit current rating up to 80kA ensuring safety under fault conditions.
Designed for easy maintenance and safe electrical isolation.
RoHS compliant, supporting environmental safety standards.

Compatibility

This NH fuse-switch disconnector is compatible with IEC fuse switch disconnectors and designed for integration within industrial switchgear assemblies using 40 mm and 60 mm bus bar systems. It supports both AC and DC applications up to 690 V AC and 440 V DC respectively, making it suitable for a wide range of power distribution systems.

Applications

Industrial power distribution and control panels.
Electrical isolation and protection in manufacturing plants.
Switchgear assemblies requiring high integrity circuit protection.
Maintenance and safety shutdown operations in electrical installations.
Renewable energy systems and infrastructure requiring robust fuse protection.

Technical Specifications

Current	250 A
Phase	Three Phase
Item number	T229879
Catalogue No	1.000.323
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10
EAN/UPC Code	4027597026707
Frequency (Hz)	50 ... 60 Hz
Rated voltage AC IEC	690 V
Rated voltage DC IEC	440 V
Ampere Rating	250 A
Utilization Category	AC 23 B @ Ue = AC 400 V; Ie = 250 A AC 22 B @ Ue = AC 500 V; Ie = 250 A AC 21 B @ Ue = AC 690 V; Ie = 200 A DC 21 B @ Ue = DC 440 V; Ie = 250 A
Switchability	3-pole switching
RoHS Compliant	Yes
AC or DC	AC/DC
Short Circuit Current Rating (SCCR)	80kA@Ue = AC 400 V; Ie = 250 A / 80kA@Ue = AC 500 V; Ie = 250 A / 50kA (3-,4-pole)@Ue = AC 690 V; Ie = 200 A
Fuse Size	1
Number of Poles	3-Pole
Degree of Pollution	3
Rated Impulse Withstand Voltage	12 kV
Rated Insulation Voltage	1000 V
Rated SC Withstand	8 kA / 1 s
Max Power dissipation of Fuse Links Pn	23 W
Max Power dissipation of Solid Links Pn	2.6 W
Power Dissipation by Ith without Fuse-Links	20 W
Rated short circuit making capacity with solid links Icm	8.2 kA
Installation Mounting	Bus bar system 40 mm and 60 mm
Product Width	185 mm
Product Length	110.5 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.09 kg
Sell Pack Width	187 mm
Sell Pack Length	248 mm
Sell Pack Height	165 mm
Product group	IEC Fuse Switch Disconnectors
Conventional Free Air thermal Current With Fuse-Links Ith	250 A
Product Weight	3.09 kg
Conventional Free Air thermal Current - Solid Links	400 A
HS Code	85365080
Country of Manufacture	Hungary
Poles	3-pole
Device Type	Fuse switch disconnector
Voltage	690 V

Frequently Asked Questions

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

The maximum ampere rating is 250 A for this NH fuse-switch disconnector.

Is this product suitable for DC applications?

Yes, it supports DC voltages up to 440 V IEC rated voltage.

What bus bar sizes can this disconnector be mounted on?

It can be installed on bus bar systems of 40 mm and 60 mm.

What type of terminals does this product use?

It uses screw M10 terminals for secure and reliable connections.

Is this product RoHS compliant?

Yes, the product is RoHS compliant.

Common Search Terms

NH fuse-switch disconnector, MULTIBLOC® Size 1, 250A fuse switch, 3-pole disconnector, industrial fuse switch, bus bar system 40mm, screw M10 terminal fuse switch, IEC fuse switch disconnectors, high current fuse switch, electrical isolation switch.

Current	250 A
Phase	Three Phase
Item number	T229879
Catalogue No	1.000.323
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10
EAN/UPC Code	4027597026707
Frequency (Hz)	50 ... 60 Hz
Rated voltage AC IEC	690 V
Rated voltage DC IEC	440 V
Ampere Rating	250 A
Utilization Category	AC 23 B @ Ue = AC 400 V; Ie = 250 A AC 22 B @ Ue = AC 500 V; Ie = 250 A AC 21 B @ Ue = AC 690 V; Ie = 200 A DC 21 B @ Ue = DC 440 V; Ie = 250 A
Switchability	3-pole switching
RoHS Compliant	Yes
AC or DC	AC/DC
Short Circuit Current Rating (SCCR)	80kA@Ue = AC 400 V; Ie = 250 A / 80kA@Ue = AC 500 V; Ie = 250 A / 50kA (3-,4-pole)@Ue = AC 690 V; Ie = 200 A
Fuse Size	1
Number of Poles	3-Pole
Degree of Pollution	3
Rated Impulse Withstand Voltage	12 kV
Rated Insulation Voltage	1000 V
Rated SC Withstand	8 kA / 1 s
Max Power dissipation of Fuse Links Pn	23 W
Max Power dissipation of Solid Links Pn	2.6 W
Power Dissipation by Ith without Fuse-Links	20 W
Rated short circuit making capacity with solid links Icm	8.2 kA
Installation Mounting	Bus bar system 40 mm and 60 mm
Product Width	185 mm
Product Length	110.5 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.09 kg
Sell Pack Width	187 mm
Sell Pack Length	248 mm
Sell Pack Height	165 mm
Product group	IEC Fuse Switch Disconnectors
Conventional Free Air thermal Current With Fuse-Links Ith	250 A
Product Weight	3.09 kg
Conventional Free Air thermal Current - Solid Links	400 A
HS Code	85365080
Country of Manufacture	Hungary
Poles	3-pole
Device Type	Fuse switch disconnector
Voltage	690 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

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£8 ex VAT · free over £200

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

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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

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

Made-to-order items

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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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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

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