Siemens Sentron Fuse switch disconnector, NH1, 3-pole, 250A Part number 3NP1143-1BC10

Product Overview

The Siemens 3NP1143-1BC10 is a SENTRON 3NP1 series fuse-switch disconnector — a 3-pole device designed for wired busbar trunk systems (8US 60 mm). It is used for safe on-load disconnection and fuse-based circuit protection in main or sub-distribution boards. With a rated current of 250 A and capability for NH0 / NH1 fuses, it is suitable for industrial and commercial power distribution systems requiring reliable disconnection and short-circuit protection.

Key Features

• 3-pole fuse-switch disconnector for busbar trunk systems (8US 60 mm)
• Compatible with NH0 / NH1 fuses
• Rated continuous current: 250 A (at 35 °C), up to 245 A (at 40 °C), 240 A (45 °C), 233 A (50 °C and above)
• Rated operational current: 250 A (AC-21B / AC-22B / AC-23B depending on load)
• Rated operational voltage (AC): up to 690 V AC; (DC) up to 440 V DC
• Let-through current (with closed switch): up to 32 kA
• Conditional short-circuit current (Iq) with high-speed fuse activation: up to 80 kA
• Flat terminal / busbar connection — suitable for busbar-mounted installation
• Sealable and lockable design for maintenance/safety use
• Compact but heavy-duty construction — suitable for industrial distribution boards and switchgear

Technical Specifications

• Article Number: 3NP1143-1BC10
• Product Family: SENTRON 3NP1 fuse-switch disconnectors
• Poles: 3 (three-pole)
• Fuse Size Compatibility: NH0, NH1
• Continuous Current Rating (Ie): 250 A (typical, at rated ambient temperature)
• Operational Current Ratings: AC-21B / AC-22B / AC-23B depending on load; DC-21B / DC-22B / DC-23B for DC circuits
• Rated Operational Voltage: up to 690 V AC / 440 V DC
• Let-through Current (Closed Switch): up to 32 kA
• Conditional Short-Circuit Current (Iq) with Fuse Activation: 80 kA
• Maximum Conductor Cross-Section (Main Contacts): 16 … 150 mm² (solid or stranded)
• Connection Type: Flat / busbar terminals, suitable for busbar mounting (rail mounting on 60 mm busbar)
• Mounting System: Busbar trunk 8US 60 mm — horizontal or vertical mounting possible
• Degree of Pollution: 3
• Insulation Voltage (Ui): 690 V
• Impulse Withstand Voltage (Uimp): 8 kV
• Protection Class (with cover / cable-lug cover): IP40
• Ambient Operating Temperature Range: –25 °C … +55 °C
• Mechanical Service Life (switching cycles): ~1,600 operations
• Enclosure Dimensions (approx.): Height 306 mm × Width 183.7 mm × Depth 142.2 mm
• Net Weight (approx.): 2.85 kg

Compliance & Certifications

• Designed according to low-voltage switchgear standards for fuse-switch disconnectors
• Suitable for industrial and commercial main or sub-distribution boards
• Sealable and lockable for maintenance, safety and compliance requirements

Applications

The 3NP1143-1BC10 is ideal as a main or branch-line fuse-switch disconnector in industrial and commercial electrical distribution systems. Typical applications include feeder protection in switchgear, sub-distribution boards, motor control centers, and commercial building distribution boards. It is suited for installations requiring robust fuse-based protection, busbar mounting, and safe disconnection under load, as well as for systems where maintenance isolation and lock-out capability are required.