Specification For The Production And Installation Of Neutral Blocks: Ensure Compliant Operation
As the core component of electrical connections, the production and installation quality of neutral block directly affects the stability and safety of the circuit system. The following outlines key operational standards from three aspects: material selection, manufacturing process, and installation specifications to ensure compliance.
1、 Material selection: Suitable for the scene, strict control of parameters
Terminal body: T2 copper or high conductivity alloy is preferred to ensure current carrying capacity. For example, the battery connection terminal needs to adopt a tubular structure with a cross slot design to enhance stability through elastic contact.
Insulation material: The outer insulation sleeve should have self extinguishing and flame-retardant properties, and the temperature resistance level should match the working environment (such as reaching 130 ℃ or above in industrial scenarios). Moisture resistant terminals should be selected for humid environments, and a 96 hour corrosion resistance test should be conducted for salt spray environments.
Wire matching: The terminal aperture should strictly correspond to the cross-sectional area of the wire. For example, ET 70 series terminals should be selected for 6mm ² wires to avoid the risk of heating caused by small terminals paired with large cross-sectional wires.
2、 Production process: Standardized process to eliminate hidden dangers
Wire stripping treatment: Use specialized wire stripping pliers, and the stripping length should be precisely controlled with an error of ≤ 0.5mm to avoid damaging the wire core. After stripping, clean the wire core with non-woven fabric to remove the oxide layer.
Crimping operation: Special crimping pliers are used, and the crimping point is located in the middle of the terminal. The crimping torque should reach 20-30N · m to ensure that the cross-section is flat and free of burrs after crimping, with a burr rate of ≤ 5%. For example, UT cold pressed terminals need to pass a tensile test, and the pulling force of 6mm ² terminals needs to be ≥ 300N.
Insulation protection: After crimping is completed, a heat shrink tubing should be placed 10mm away from the insulation layer on the wire, and the color should be selected according to the circuit type (such as AC yellow/green/red, DC brown/blue), and heated and shrunk to a snug fit.
3、 Installation specifications: Reasonable layout, clear labeling
Layout principle: The terminal block should be installed at the edge of the circuit board, leaving sufficient space; Strong and weak electrical terminals should be arranged separately and isolated with empty terminals or reinforced insulation partitions; A blank terminal should be left between the positive and negative power terminals to prevent short circuits.
Fixed method: When installing the terminal box, it is necessary to use aluminum pressure plates and screwdrivers to tighten and ensure the stability of the terminals; Spring type terminals need to be inserted with wires after pressing a button or moving a stopper to avoid poor contact caused by forced insertion.
Identification management: All terminals must be labeled with numbers, names, purposes, and operating positions, with clear and non fading handwriting. For example, in industrial scenarios, "handle wires" can be used to identify multiple terminals for easy insertion and maintenance.
4、 Compliance Verification: Testing and Maintenance
Contact resistance test: Use a micro ohmmeter to measure the terminal contact resistance, ensuring that the temperature rise is ≤ 30K (UL 310 standard).
Tensile testing: Regularly inspect the terminal pulling force to ensure compliance with design requirements.
Environmental adaptability testing: Terminal corrosion resistance needs to be tested quarterly in salt spray environments, and insulation material temperature resistance levels need to be verified in high temperature scenarios.
