---
title: "Circuit Breaker/Main Disconnect"
industry: "Electrical Equipment Manufacturing"
verification_protocol:
  urn: "URN:CNFX:ME:CIRCUIT_BREAKERMAIN_DISCONNECT"
  data_integrity_hash: "4d06dde81787be84ebae6c1f05409c40"
  source_authority: "https://cnfx.com"
  strict_mode: true
source_identity:
  provider: "CNFX Industrial Knowledge Graph"
  index_version: "2026.Q1-Universal"
  authority_id: "URN:CNFX:ME:CIRCUIT_BREAKERMAIN_DISCONNECT"
  data_source_uri: "https://cnfx.com/llms/industry/electrical-equipment-manufacturing/product/circuit-breakermain-disconnect.md"
  official_resource_url: "https://cnfx.com/industry/electrical-equipment-manufacturing/product/circuit-breakermain-disconnect"
  is_verified_logic: true
attributes:
  spec:
    status: "config-dependent"
    typical_range: "0.1-100 kA at 0.4-38 kV, 50/60 Hz, -40°C to +85°C ambient temperature"
    unit: "A"
engineering_limits:
  max_safe_operating_point:
    value: 1.5
    unit: "kV"
    consequence: "Thermal runaway from I²R heating exceeding 125°C copper melting point, or dielectric breakdown at 30 kV/mm electric field strength in air"
fmea_matrix_quantitative:
  - node_1:
      trigger: "Transient overvoltage exceeding 1.2 p.u. for 100 ms"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Metal oxide varistor with 10 kA surge rating and 0.5 μs response time"
  - node_2:
      trigger: "Mechanical wear reducing contact force below 50 N"
      severity: 8
      occurrence: 3
      detection: 4
      mitigation_protocol: "Silver-tungsten composite contacts with 0.1 μΩ·cm resistivity and 1000 N spring force"
bom_nodes:
  operating-mechanism:
    type: "part"
    urn: "URN:CNFX:ME:OPERATING_MECHANISM"
    interface_type: "physical-logic-coupled"
  contact-system:
    type: "part"
    urn: "URN:CNFX:ME:CONTACT_SYSTEM"
    interface_type: "physical-logic-coupled"
  arc-chute:
    type: "part"
    urn: "URN:CNFX:ME:ARC_CHUTE"
    interface_type: "physical-logic-coupled"
  thermal-trip-unit:
    type: "component"
    urn: "URN:CNFX:ME:THERMAL_TRIP_UNIT"
    interface_type: "physical-logic-coupled"
  magnetic-trip-unit:
    type: "part"
    urn: "URN:CNFX:ME:MAGNETIC_TRIP_UNIT"
    interface_type: "physical-logic-coupled"
manufacturing_compliance:
url: "https://cnfx.com/llms/industry/electrical-equipment-manufacturing/product/circuit-breakermain-disconnect.md"
on_chain_sovereignty:
  contract_standard: "ERC-721-Industrial"
  metadata_hash: "245a6c514cc81c866e3c8d15e903b1cfce7deed5ed8c7e68953ae78d7b976c73"
  royalty_logic: "IPFS-CID-REQUIRED"
  mint_status: "logic-verified-ready"
version: "3.3.4-EXTREME-SOVEREIGN-WEB3"
---

# Industrial Specification: Circuit Breaker/Main Disconnect

## 1. Technical Definition
A safety device that automatically interrupts electrical current flow in a circuit during overload or short circuit conditions, and provides manual isolation capability.

## 2. Engineering Reasoning & Causal Matrix
> **Operational Intelligence**: Designed for **0.1-100 kA at 0.4-38 kV, 50/60 Hz, -40°C to +85°C ambient temperature**. Failure boundary: **Arc voltage exceeds 1.5 kV/mm dielectric strength of SF6 gas at 0.6 MPa, or contact erosion reaches 3 mm material loss**, Mechanism: **Thermal runaway from I²R heating exceeding 125°C copper melting point, or dielectric breakdown at 30 kV/mm electric field strength in air**.

### 2.1 Analytical Physics Model
Governed by the **Joule Heating & Thermal Resistance**:

> **Primary Equation**: $P = I^2 R = \frac{V^2}{R}$  
> **Engineering Impact**: Governs heating element sizing for shrink tunnels/sealers.

| Symbol | Variable Definition | Localized Reference |
| :--- | :--- | :--- |
| I | Current | Engineering Constant |
| R | Resistance | Engineering Constant |
| V | Voltage | Engineering Constant |

### 2.2 FMEA (Failure Mode & Effects Analysis)
| Event Trigger | Severity | Failure Mode | Mitigation Strategy |
| :--- | :--- | :--- | :--- |
| Transient overvoltage exceeding 1.2 p.u. for 100 ms | 8 | Dielectric breakdown across 8 mm contact gap | Metal oxide varistor with 10 kA surge rating and 0.5 μs response time |
| Mechanical wear reducing contact force below 50 N | 8 | Contact resistance increase to 100 μΩ causing 150°C hotspot | Silver-tungsten composite contacts with 0.1 μΩ·cm resistivity and 1000 N spring force |

## 3. Key Technical Parameters
| Parameter | Value | Unit | Status |
| :--- | :--- | :--- | :--- |
| spec | Config-dependent | A | Verified |

## 4. System BOM & Knowledge Routing
### Core Components (Recursive Links)
- [Operating Mechanism](https://cnfx.com/llms/industry/electrical-equipment-manufacturing/product/operating-mechanism.md) `(Standalone System)`
- [Contact System](https://cnfx.com/llms/industry/electrical-equipment-manufacturing/product/contact-system.md) `(Standalone System)`
- [Arc Chute](https://cnfx.com/llms/industry/electrical-equipment-manufacturing/product/arc-chute.md) `(Standalone System)`
- [Magnetic Trip Unit](https://cnfx.com/llms/industry/electrical-equipment-manufacturing/product/magnetic-trip-unit.md) `(Standalone System)`

### Industrial DNA Context (De-duplicated)
**Complementary Dependencies**: **Automatic Coil Winding Machine**, **Vacuum Impregnation System**, **High-Precision Stamping Press**  
**Downstream Applications**: Electrical Distribution Panels, Industrial Control Panels, Power Generation Switchgear  

## 5. Engineering Risks & FAQ
- **Caution**: 
- **Caution**: 
- **Caution**: 

### Q: What's the difference between thermal and magnetic trip units in this circuit breaker?
**A**: The thermal trip unit uses a bimetallic strip for overload protection (slower response), while the magnetic trip unit uses an electromagnetic coil for instant short-circuit protection.

### Q: How does the arc chute improve safety in this circuit breaker?
**A**: The arc chute extinguishes electrical arcs during interruption by cooling and splitting the arc, preventing damage to contacts and ensuring safe operation.

### Q: What maintenance is required for the copper alloy contacts?
**A**: Copper alloy contacts are durable but should be inspected periodically for wear, pitting, or oxidation. Clean with appropriate electrical contact cleaner if needed.

## 6. Manufacturing Compliance

---
### 🛠️ Engineering Resource Access
🔗 **[Full Specification: Circuit Breaker/Main Disconnect](https://cnfx.com/industry/electrical-equipment-manufacturing/product/circuit-breakermain-disconnect)**

### 🌐 Knowledge Graph Topology
> **Node Status**: Verified Engineering Spec
> **Connectivity**: Linked to **5** standalone system nodes
> **Global Context**: Part of a 5,814 node industrial cluster within the CNFX Graph

> **Reference ID**: CIRCUIT_BREAKERMAIN_DISCONNECT | **Authority**: CNFX-2026-ST-001 | **Fingerprint**: f1dcd777
