Terminal block production and installation tutorial: from beginner to proficient

Terminal blocks are the core components of electrical connections, widely used in distribution boxes, control cabinets, and equipment circuits. Mastering its production and installation techniques can significantly improve the safety and stability of electrical systems. The following provides a step-by-step explanation of key points, from basic operations to advanced techniques.

1、 Preparation of tools and materials

tool list

Wire stripping pliers (select 0.5-6mm ² size according to wire diameter)

Wire crimping pliers (matching terminal models, such as OT type, U type, pin type)

Diagonal pliers (trimming wire ends), multimeter (testing conductivity)

Insulation tape or heat shrink tubing (to protect exposed conductors)

Material selection

Terminal type: Select according to the load current (e.g. 2.5mm ² terminal for 10A, 6mm ² terminal for 32A)

Wire specification: Match with terminal current carrying capacity to avoid "small horse pulling big car"

Identification sleeve: print circuit number for easy maintenance in the later stage

2、 Production process: precise operation to eliminate hidden dangers

Strip the wire

Use wire stripping pliers to remove the insulation layer, with a length equal to the length of the terminal crimping area plus 2mm (with adjustment allowance reserved)

Example: The stripping length of a 6mm ² wire is about 12mm to avoid short circuits caused by excessively long exposed copper wires

crimping

Insert the wire into the crimping area of the terminal, ensuring that the copper wire is fully embedded

Apply even pressure using a crimping tool, and hear a "click" sound to indicate that the crimping is in place

Key standard: The tensile strength of the terminal after crimping should be ≥ 80% of the rated tensile strength of the wire

Insulation treatment

Insert the heat shrink tubing (the length should cover the terminal+10mm insulation layer), and use a hot air gun to evenly heat and shrink it

Or wrap insulation tape and use the "half stack wrapping method" to wrap 3-5 layers

3、 Installation standard: Safety first, efficiency first

Terminal block fixation

When installing with a guide rail, clip the terminal block into the 35mm standard guide rail to ensure that the buckle is securely locked

Outdoor or humid environments require the installation of protective covers to prevent condensation from causing short circuits

Wiring sequence

Following the principle of "left zero, right fire, ground wire", the distance between strong and weak electrical terminals should be ≥ 50mm

Multiple wires need to be tinned before crimping to avoid oxidation and increase in contact resistance

Identification management

Use a label machine to print circuit numbers, paste them under the terminals or use identification sleeves

Example: Lighting circuit labeled "L1-1", air conditioning circuit labeled "AC-3"

4、 Common Problems and Solutions

Terminal heating

Reason: Poor crimping, wire overload, poor oxidation contact

Solution: Re press the terminals, check if the load current exceeds the standard, and clean the contact surface

Short-circuit fault

Reason: Insulation damage, exposed wire ends, insufficient terminal spacing

Solution: Wrap the damaged area with insulation tape, adjust the terminal layout, and add insulation barriers

5、 Advanced skills: Improve efficiency and reliability

Batch production

By using an automatic wire stripping and crimping machine, the wire stripping, crimping, and testing processes can be completed simultaneously, increasing efficiency by three times

Pre assembly process

Before assembling the distribution box, crimp and label the terminals and wires in advance to reduce on-site operation time

Quality Inspection

Use a tensile tester to test the terminal's tensile strength, and use a megohmmeter to measure the insulation resistance (≥ 0.5M Ω)

Summary: The production of wiring terminals should follow the three principles of "precise wire stripping, firm crimping, and reliable insulation", and pay attention to layout specifications and clear labeling during installation. By standardizing operations and conducting regular inspections, the electrical failure rate can be significantly reduced, providing a guarantee for the stable operation of the system.