MERSEN FUSE MB1 250A 3P 1.003.134 1.003.134

3-pole NH fuse-switch disconnector supporting up to 250A with electronic fuse monitoring and compatibility with 40mm and 60mm bus bar systems.

SKU: R1023055Alt SKU: 1.003.134MPN: R1023055

List Price £871.45 ex VAT

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

Optimised for modern low-voltage distribution, this 3-pole NH fuse-switch disconnector supports up to 250A and integrates seamlessly within 40mm bus bar systems. Its robust M10 screw terminals ensure secure electrical connections for demanding industrial environments.

Engineered for reliability and safety, the MULTIBLOC® system enables fast, safe fuse-switching with clear electrical monitoring. This unit is ideal for applications requiring precise protection and rapid maintenance in commercial and industrial installations.

Product Code: R1023055

Key Benefits

High current rating of 250A suitable for demanding industrial applications.
3-pole switching ensures comprehensive circuit isolation and protection.
Compatible with 40mm and 60mm bus bar systems for flexible installation.
Electronic fuse monitoring (ESÜ) installed for enhanced safety and status indication.
Robust M10 screw connections provide secure and reliable electrical contact.
Designed to meet IEC standards with high short circuit current rating (up to 80kA).
Compact dimensions for space-efficient panel integration.

Compatibility

This fuse-switch disconnector is compatible with NH fuse size 1 and designed for use with both AC and DC systems up to 690 V AC and 440 V DC. It integrates with 40mm and 60mm bus bar systems and supports solid links and fuse links, providing versatility for various electrical distribution setups.

Applications

Industrial low-voltage power distribution panels.
Commercial electrical installations requiring reliable circuit protection.
Control and distribution boards in manufacturing plants.
Maintenance and safety switching in electrical networks.
Renewable energy systems with DC and AC protection needs.

Technical Specifications

Current	250 A
Phase	Three Phase
Item number	R1023055
Catalogue No	1.003.134
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10 elec mon.
EAN/UPC Code	9008567006382
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
Design Details	with electronic fuse monitoring ESÜ installed (rated voltage = 525VAC)
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	129 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.14 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	3.14 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 device supports a maximum current rating of 250A, suitable for industrial low-voltage applications.

Is this product compatible with both AC and DC systems?

Yes, it is designed for use in AC systems up to 690 V and DC systems up to 440 V.

What type of fuse size does this disconnector support?

This unit supports NH fuse size 1, enabling standardised protection options.

Can this fuse-switch disconnector be mounted on different bus bar sizes?

Yes, it is compatible with bus bar systems of 40mm and 60mm widths for flexible installation.

Does the product include any electronic monitoring features?

It includes electronic fuse monitoring (ESÜ) installed, providing enhanced safety and status indication.

Common Search Terms

NH fuse switch disconnector, MULTIBLOC fuse switch, 250A fuse holder, 3-pole fuse switch, bus bar fuse switch 40mm, electronic fuse monitoring, industrial fuse switch, IEC fuse switch disconnector, low voltage fuse switch, screw terminal fuse switch

Current	250 A
Phase	Three Phase
Item number	R1023055
Catalogue No	1.003.134
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10 elec mon.
EAN/UPC Code	9008567006382
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
Design Details	with electronic fuse monitoring ESÜ installed (rated voltage = 525VAC)
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	129 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.14 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	3.14 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.

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