MERSEN FUSE MB1 250A 3P 1.000.831 1.000.831

Robust NH fuse-switch disconnector with electromechanic fuse monitoring MZS for reliable circuit protection and isolation in industrial applications. Designed for bottom fitting and panel mounting with secure screw M10 connections.

SKU: T1023057Alt SKU: 1.000.831MPN: T1023057

List Price £738.75 ex VAT

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£738.75

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

The NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-pole offers robust circuit protection and reliable isolation for demanding industrial applications. Designed for bottom fitting and panel mounting, it features secure screw M10 terminations for stable, low-resistance connections.

This unit ensures rapid and safe fuse replacement while maintaining IP protection and compliance with IEC standards. Its compact construction facilitates straightforward installation and integration into modern switchgear assemblies.

Product Code: T1023057

Key Benefits

Robust circuit protection with reliable isolation for industrial environments.
Secure screw M10 terminations ensure stable, low-resistance electrical connections.
Compact design enables easy installation in switchgear panels.
Rapid and safe fuse replacement reduces downtime and maintenance effort.
Complies with IEC standards and offers high short circuit current ratings for safety.
Equipped with electromechanic fuse monitoring (MZS) for enhanced operational safety.

Compatibility

This fuse-switch disconnector is compatible with NH Size 1 fuse links and designed for integration into IEC-compliant switchgear assemblies. It supports AC systems up to 690 V and is suitable for use with 3-pole switching configurations in industrial electrical installations.

Applications

Industrial power distribution and control panels.
Protection and isolation of electrical circuits in manufacturing plants.
Switchgear assemblies requiring compact and reliable fuse-switch disconnectors.
Maintenance and safety switching in electrical distribution systems.
Electrical installations demanding high short circuit current ratings and IEC compliance.

Technical Specifications

Current	250 A
Phase	Three Phase
Item number	T1023057
Catalogue No	1.000.831
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bottom Fitting/panel Connection Screw M10 elecmec mon.
EAN/UPC Code	4027597023454
Frequency (Hz)	50 ... 60 Hz
Rated voltage AC IEC	690 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
Short Circuit Current Rating (SCCR)	80kA@Ue=AC 400 V;Ie=250 A / 80kA@Ue=AC 500 V;Ie=250 A / 80kA (1-,2-pole)@Ue=AC 690 V;Ie=200 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	13 W
Power Dissipation by Ith without Solid Links	33 W
Rated short circuit making capacity with solid links Icm	8.2 kA
Installation Mounting	Bottom Fitting/panel
Product Width	185 mm
Product Length	186.5 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.13 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	3.13 kg
Conventional Free Air thermal Current - Solid Links	400 A
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 AC IEC for this product is 690 V.

Can this unit be used in DC applications?

This specific model is designed for AC applications only.

What type of fuse monitoring does this product include?

It includes electromechanic fuse monitoring MZS with galvanic isolation.

What is the short circuit current rating (SCCR) of this product?

The SCCR is 80kA at AC 400 V and AC 500 V for 1- and 2-pole configurations, and 50kA at AC 690 V for 3- and 4-pole configurations.

How is this fuse-switch disconnector mounted?

It is designed for bottom fitting and panel mounting.

Common Search Terms

NH fuse switch disconnector, MULTIBLOC Size 1, 250A fuse switch, 3-pole fuse switch, IEC fuse switch disconnector, electromechanic fuse monitoring, panel mounting fuse switch, bottom fitting fuse switch, industrial circuit protection.

Current	250 A
Phase	Three Phase
Item number	T1023057
Catalogue No	1.000.831
Description	NH fuse-switch disconnector MULTIBLOC® Size 1 250A 3-Pole switching Bottom Fitting/panel Connection Screw M10 elecmec mon.
EAN/UPC Code	4027597023454
Frequency (Hz)	50 ... 60 Hz
Rated voltage AC IEC	690 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
Short Circuit Current Rating (SCCR)	80kA@Ue=AC 400 V;Ie=250 A / 80kA@Ue=AC 500 V;Ie=250 A / 80kA (1-,2-pole)@Ue=AC 690 V;Ie=200 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	13 W
Power Dissipation by Ith without Solid Links	33 W
Rated short circuit making capacity with solid links Icm	8.2 kA
Installation Mounting	Bottom Fitting/panel
Product Width	185 mm
Product Length	186.5 mm
Product Height	246 mm
Sell Pack Quantity	1 EA
Sell Pack Weight	3.13 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	3.13 kg
Conventional Free Air thermal Current - Solid Links	400 A
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.

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

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Mon–Fri, 8am–5pm

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

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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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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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