Description

Send Inquiry

Product Overview

The Neutral Terminal 250A 16 To 50sqmm is a single-pole neutral (N) connection point for the middle of the low-voltage range - the band where commercial distribution boards, motor control centres and small PV AC combiner cabinets sit.

Two things go wrong there. A terminal borrowed from a 400 A frame arrives with a footprint the cabinet was never laid out for; drop in a lighter strip instead, and the joint runs warm once the neutral starts carrying unbalanced load.

It is dimensioned around a 16–50 mm² conductor range: 250 A continuous, one pole, several neutral points on one base, on a glass-reinforced PA66 insulator rated above 20 kV/mm.

Technical Specifications

The electrical rows are this model's own published figures. The commercial rows are series reference from pages already delivered in this range, because this page publishes none of them.

Item	Specification
Function	Single-pole dedicated neutral (N) terminal block for three-phase four-wire systems
Rated Current	250 A continuous duty - ambient and installation basis not published, see the production notes
Load Basis	250 A rates the terminal body, not each outlet. Every connection point carries only what its own conductor allows, so send the branch loads you intend to run and we confirm the fit
Rated Voltage	400 V AC
Poles	1 pole, multiple neutral connection points on one body
Wire Range	16 mm² to 50 mm², solid or stranded copper
Conductor	High-purity electrolytic copper blocks, precision-machined
Surface Finish	Tin plated - plate thickness not published, confirm the call-up
Insulation Material	Glass-reinforced polyamide 66 (PA66+GF)
Dielectric Strength	Above 20 kV/mm
Insulation Resistance	Above 100 MΩ at 500 V DC
Operating Temperature	−25 °C to +85 °C
Terminal Screws	M6 steel
Screw Torque	2.0 N·m to 2.5 N·m as published; the 400 A page in this range lists 5–7 N·m for its own M6 screws, see production note 3
Contact Resistance	Not published for this model; the 400 A page states 0.2 mΩ maximum - series reference, confirm
Withstand Voltage	Not published for this model; the same range tests at AC 2500 V for 1 minute - series reference, confirm
Mounting	Pre-drilled holes for direct fixing to the panel plate or busbar
Standards	IEC 60947-1 and GB 7251.1 as published - see production note 4
Customization	Terminal configuration, mounting hole pattern, screw specification and branding produced to your drawing; OEM and ODM available
Quality Control	Electrical performance, mechanical strength and corrosion resistance testing on every batch
MOQ	20 pieces for standard products, low enough to trial before a project order
Lead Time	7 to 10 days standard; 15 to 20 days custom
Quality Guarantee	12 to 24 months, counted from the shipment date
Manufacturing Standard	ISO 9001 quality management system
Packaging	30 pieces per carton, 3.2 kg gross per carton
Delivery Ports	Ningbo Port / Shanghai Port
Quote Turnaround	Within 24 hours of receiving the drawing

Core Advantages

Four points decide whether a 250 A neutral point fits the cabinet you already build.

Dimensioned For The 250 A Band

Rated 250 A continuous on a 16–50 mm² range, this is a body built for the middle of the range, not a 400 A frame with a smaller label - so the neutral point stops driving enclosure size.

A Compact Body, Judged By Weight

The published packing figure is the honest proxy: 30 pieces to a 3.2 kg carton, roughly 100 g per unit - light hardware in this class, less weight to mount and ship.

A Torque Value For The Work Instruction

2.0–2.5 N·m on M6 screws is a figure a panel shop can write into the assembly instruction and audit on the floor - a loose joint is the usual reason a neutral runs warm.

Tin Where The Joint Closes

Tin plating keeps the copper contact faces from oxidising in humid or corrosive plant air, so the joint does not grow warmer year on year.

Wire Cage Terminal vs Traditional Brass Terminal

The heading comes from the reference template; this is a screw-clamped copper block, so the table compares it with a traditional brass neutral strip. See production note 6.

What Changes	This Tinned Copper Neutral Terminal	Traditional Brass Neutral Strip
Conductor material	High-purity electrolytic copper blocks, precision-machined	Brass alloy, lower conductivity by composition
Current class	250 A continuous, published	Usually unrated on the strip itself
Insulated body	Glass-reinforced PA66 base, above 20 kV/mm dielectric strength	Bare metal on separate stand-off insulators
Contact faces	Tin plated over copper	Bare brass, oxide-prone
Torque to apply	2.0–2.5 N·m on M6, published	Set by feel
Wire range	16–50 mm², solid or stranded copper	Fixed hole spacing, adapters needed
Connection points	Several neutral points on one single-pole body	One conductor per stud

Professional Production Process

The process runs in six operations, and each one closes with a number written down.

Copper block stock is checked for grade on receipt.

Each block is machined to the drawing, and the machined face is measured.

The PA66 base is moulded and inspected for flash and dimensional drift.

Blocks enter the tin bath as a batch, with coating thickness sampled.

Screws are assembled, and every connection point is proofed.

Units pass electrical, mechanical and corrosion testing before packing.

Material & Surface Treatment Options

Two material decisions are worth settling before tooling, because both are hard to change afterwards.

Glass-Reinforced PA66 Base

The insulator carries a dielectric strength above 20 kV/mm and insulation resistance over 100 MΩ at 500 V DC, holding the conductive blocks clear of the mounting surface.

Electrolytic Copper Blocks, Tin Plated

High-purity electrolytic copper keeps the joint cool, and the tin plate protects the faces where oxidation would otherwise raise resistance year on year.

Application Scenarios

Three cabinet types where the 250 A neutral point decides the layout.

Commercial Distribution Boards And Panelboards

Three-phase four-wire boards in commercial buildings, where several neutral conductors leave one small body instead of a row of separate studs.

Motor Control Centres And Industrial Control Panels

Control panels feeding mixed loads, where harmonics and unbalanced single-phase circuits push neutral current up in this band.

PV AC Combiners And Small Storage Cabinets

AC combiner and small storage cabinets on rooftops and behind-the-meter sites, where the neutral path has to be rated rather than improvised.

Frequently Asked Questions

Q: What does the 250 A rating actually cover?

A: It rates the single-pole body on a 16–50 mm² copper conductor. No ambient or installation basis is published, and each point carries only what its own conductor allows - send the branch loads and we confirm the fit.

Q: How does it compare in size with a neutral terminal one size up?

A: It is a body dimensioned for the middle of the range, not a larger frame with a smaller label. The packing figure is 30 pieces to a 3.2 kg carton; ask for the envelope drawing and check it against your panel layout.

Q: What conductors and torque does it take?

A: Solid or stranded copper from 16 to 50 mm², clamped by M6 steel screws at 2.0–2.5 N·m and rated 400 V AC. A page in the same range lists 5–7 N·m for its own M6 screws, so we confirm per drawing.

Q: Can it be built to our drawing?

A: Terminal configuration, mounting hole pattern, screw specification and branding all go to your drawing, and a first article travels with the sample before the run starts.

Q: What is the MOQ, and how fast is a quotation?

A: Standard MOQ is 20 pieces, low enough to trial before a project order. Standard products leave in 7 to 10 days and custom builds in 15 to 20, against a 12 to 24 month guarantee. Quotes come back within 24 hours.