How Its Made Assembly Wire Harness

Wire Harness Assembly Process

1. Design Phase

1. Schematic & Layout Design

• Schematic: Illustrates electrical connections, including all terminals, wire types, lengths, and component positions.

• Layout: Plans the physical routing of the harness within the equipment, considering space constraints, environmental conditions (temperature, humidity, vibration), and power requirements.

2. Material Selection

• Wires: Choose conductor material (copper/aluminum), insulation type (PVC/XLPE/silicone), and gauge based on voltage, current, and environmental demands.

• Connectors: Select connector types (e.g., plug-in, screw-mounted) matching equipment interfaces, ensuring locking mechanisms (e.g., secondary locks) function correctly.

• Protective Materials: Prepare heat-shrink tubing, corrugated sleeves, zip ties, etc., for insulation and mechanical protection.

2. Material Preparation

1. Wire Cutting

• Cut wires to specified lengths, adding 5–10mm allowance for installation errors.

2. Terminal Preparation

• Verify terminal types (e.g., ring, fork, pin) match connector pin positions and check for deformation in the crimping zone.

3. Connectors & Accessories

• Gather connectors, positioning plates, labels, and contact grease (e.g., Chemtres) for assembly.

3. Assembly Process

1. Stripping & Crimping

• Stripping: Use wire strippers to remove insulation without damaging the conductor.

• Crimping: Attach terminals to stripped conductors using crimping tools, ensuring secure electrical contact.

2. Sub-Assembly & Electrical Testing

• Sub-Assembly: Prepare wire segments based on positioning plates to minimize waste.

• Electrical Testing: Conduct continuity checks to detect opens or shorts.

3. Routing & Pin Insertion

• Routing: Lay wire segments flat on positioning plates, starting with simple zones and progressing to complex areas.

• Pin Insertion: Insert uncrimped terminals into connector pins using a "push-listen-pull-back" method to ensure proper seating.

4. Bundling & Fixing

• Bundling: Secure wires with zip ties or lacing tape per positioning plate instructions, starting at dual-wire origins.

• Fixing: Ensure bundles are parallel, stable, and free of tangles, avoiding connector interference with positioning pins.

5. Covering & Protection

• Covering: Wrap exposed wires with heat-shrink tubing or corrugated sleeves for insulation and abrasion resistance.

• Fixing: Use tape or sleeves to secure the harness, preventing movement or wear during operation.

4. Testing & Inspection

1. Electrical Testing

• Verify wire connections for continuity, shorts, and miswiring using specialized equipment.

2. Full Inspection

• Visual Check: Confirm terminals/connectors are within tolerance, bundles are uniform, and components are correctly assembled.

• Physical Test: Check for wiring errors, exposed wires, or loose connections.

3. Continuity Rate Verification

• Ensure 100% conductivity with no shorts or misroutes.

5. Packaging & Storage

1. Packaging

• Package tested harnesses with labels, manuals, and quality certificates.

2. Storage

• Approve harnesses for storage via OQC (Outgoing Quality Control) inspection, pending installation or shipment.

6. Key Considerations

1. Precision

• Follow design specifications for cutting, routing, and crimping to ensure correct connections and lengths.

2. Security

• Ensure terminals and wires are firmly attached to prevent failures.

3. Insulation

• Apply complete protective materials to avoid short circuits or leaks.

4. Maintainability

• Design harnesses for easy troubleshooting and component replacement.

5. Durability

• Ensure harnesses withstand environmental conditions and prolonged use.

6. Quality Management

• Adhere to ISO 9001 or similar standards to maintain excellence at every step.

This structured approach ensures high-quality wire harnesses that meet stringent safety and performance requirements across industries like automotive, aerospace, and industrial automation.