MERSEN FUSE MB1 250A 3P 1.000.855 1.000.855

Reliable and versatile NH fuse-switch disconnector with 250A rating, 3-pole switching, and compatibility with 40mm and 60mm bus bar systems. Features electromechanic fuse monitoring and M10 screw connections.

SKU: M1023051Alt SKU: 1.000.855MPN: M1023051

List Price £915.54 ex VAT

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

Engineered for reliability and versatility, the NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole provides safe switch-off and isolation in demanding industrial and commercial distribution systems. Its robust design, featuring a 250A rating and compatibility with 40mm bus bar systems, ensures optimal performance in high-load applications.

Equipped with secure M10 screw connections for straightforward installation and lasting electrical contact, this device offers enhanced operator safety and minimal maintenance. Ideal for panel builders and OEMs seeking cost-effective, standard-compliant switching solutions.

Product Code: M1023051

Key Benefits

Reliable disconnection and isolation with 3-pole switching for enhanced safety.
High ampere rating of 250A suitable for demanding industrial applications.
Compatible with 40mm and 60mm bus bar systems for installation flexibility.
Robust M10 screw connections ensure secure and durable electrical contact.
Electromechanic fuse monitoring (MZS) with galvanic isolation for improved operational safety.
Compact dimensions facilitate integration into various panel designs.

Compatibility

This fuse-switch disconnector is compatible with NH fuse links size 1 and designed for use in IEC standard fuse switch disconnectors. It supports AC and DC applications up to 690 V AC and 440 V DC, making it suitable for a wide range of industrial electrical distribution systems.

Applications

Industrial power distribution panels.
Commercial electrical switchgear assemblies.
OEM equipment requiring reliable fuse-switch disconnection.
Electrical isolation in maintenance and safety procedures.
Systems requiring high short circuit current ratings and thermal current capacities.

Technical Specifications

Current	250 A
Phase	Three Phase
Item number	M1023051
Catalogue No	1.000.855
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10 elecmec mon.
EAN/UPC Code	9008567002131
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
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 electromechanic fuse monitoring MZS installed (galvanic isolation)
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	186.5 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.8 kg
Sell Pack Width	208 mm
Sell Pack Length	262 mm
Sell Pack Height	185 mm
Product group	IEC Fuse Switch Disconnectors
Conventional Free Air thermal Current With Fuse-Links Ith	250 A
Product Weight	3.8 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 rated voltage for this fuse-switch disconnector?

The maximum rated voltage is 690 V AC and 440 V DC according to IEC standards.

Can this product be used in both AC and DC circuits?

Yes, it is designed for use in both AC and DC applications.

What type of fuse size does this disconnector accommodate?

This device is compatible with NH fuse links size 1.

Is the product suitable for high short circuit current ratings?

Yes, it has a short circuit current rating (SCCR) of up to 80kA at 400 V and 500 V AC.

What kind of mounting system does this product support?

It supports bus bar systems of 40 mm and 60 mm for installation.

Common Search Terms

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

Current	250 A
Phase	Three Phase
Item number	M1023051
Catalogue No	1.000.855
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bus bar system 40mm Connection Screw M10 elecmec mon.
EAN/UPC Code	9008567002131
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
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 electromechanic fuse monitoring MZS installed (galvanic isolation)
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	186.5 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.8 kg
Sell Pack Width	208 mm
Sell Pack Length	262 mm
Sell Pack Height	185 mm
Product group	IEC Fuse Switch Disconnectors
Conventional Free Air thermal Current With Fuse-Links Ith	250 A
Product Weight	3.8 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

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