Purchase of multi-colored car wires begins with the verification of certificates of conformity GOST or TU, as it is the marking of the insulation that guarantees the safety of operation of the on-board network under a voltage of 12 volts. The use of cheap technical PVC insulation, not intended for cars, often leads to cracking of the material in the cold and short circuit when the body vibrates. Unlike household wiring, cable It must withstand contact with aggressive liquids such as gasoline, oil and brake fluid without losing its dielectric properties.
When ordering materials for vehicle electrification, it is critical to pay attention to the material of the vein, since aluminum in the moving units quickly breaks down from metal fatigue. The best solution is to copper-wire, passed the process of tingling, which protects the contacts from oxidation and provides a stable current even in conditions of high humidity. Color coding in this case serves not only aesthetics, but also a safety standard that allows you to quickly identify the power chain, ground or signal line during repair.
The modern market offers a wide range of products, where colourful It is made of oil-resistant and benzo-resistant composites that retain elasticity in the temperature range from -40 to +105 degrees Celsius. Buying a bay or cable cut, it is necessary to visually assess the quality of the twisting veins and the uniformity of color, since fading may indicate a violation of production technology or the use of secondary raw materials. The right choice of section and type of insulation directly affects the fire safety of the car and the durability of the installed additional equipment.
Criteria for the choice of material veins and insulation
The basis of any electrical cable is a conductive vein, and in the automotive industry, copper has become the de facto standard due to its high electrical conductivity and flexibility. When buying, it is important to distinguish between ordinary copper wire and lawn wire, which is covered with a thin layer of tin to protect against corrosion, which is especially important for regions with a humid climate or salty roads. Rained copper It is much more expensive, but its use in chains exposed to moisture is justified by the extended service life of the wiring.
The insulating layer performs the function of a barrier between the current-carrying part and the car body, which is the mass (minus). For automotive purposes, wires with polyethylene insulation or ordinary PVC tubes are categorically not suitable, since they melt when heated and crack in the cold. Specialized wire-wire They are made of PVC plastics that are resistant to oil products, ultraviolet light and mechanical abrasion.
An important aspect is the thermal resistance of the insulation, which must withstand heating from the running engine or proximity to the exhaust system without deformation. When choosing between different brands, you should give preference to manufacturers that indicate the operating temperature range on the label or in the technical documentation. Ignoring this parameter can lead to melting of insulation and fire in the underhood space.
Color marking standards and their meaning
Color-labeled wires in a car are a versatile language that allows electricians to quickly navigate complex wiring harnesses. Although there is no single world standard, in the practice of repair and tuning, a certain color coding has developed, which is useful to observe when laying new lines on your own. For example, red is traditionally associated with battery power, while black or brown is associated with mass.
- 🔴 Red - constant power supply (+12V) from the battery, the main power chains.
- ⚫ Black - grounding (mass), connection with the car body.
- 🟡 Yellow – often used for ignition circuits or signal lines.
- 🔵 Blue - control of additional equipment (amplifiers, relays).
- 🟢 Green: signal chains, sensors, sometimes chains of dimensions.
The use of multicolored wires allows you to create a logical structure of electrical wiring, which greatly simplifies the search for faults in the future. If all the wires will be the same color, for example, black, then if you break down, you will have to “name” each vein a multimeter, spending hours on diagnosis. Color differentiation Reduces the likelihood of error when connecting new devices, such as alarms, multimedia or additional lighting.
Non-standard colors in imported cars
In cars of European and Japanese production, the color range may differ from the generally accepted. For example, a pink wire may indicate the power of the tape recorder, and an orange wire may indicate a backlight chain. Always check the electrical circuits (wiring diagrams) of a particular car before interfering with the regular wiring.
Calculation of the wire cross section by load power
The correct choice of the cable cross section is the key to the stable operation of electrical equipment and the absence of overheating of the wiring. The cross-section is determined in square millimeters (mm2) and directly depends on the current consumed by the connected device and the length of the chain section. Neglecting calculations and using thin wire for a powerful consumer, for example, an amplifier or winch, will lead to a voltage drop and a fire hazard situation.
For accurate selection, it is necessary to know the maximum load current and length of the wire from the power source to the consumer. The longer the track, the greater the resistance and the thicker the wire must be to compensate for voltage losses. Below is a help table to help you choose the best copper-wire for the 12B onboard network.
| Section (mm2) | Max. current (A) | Permissible length at 10A (m) | Typical application |
|---|---|---|---|
| 0.5 | 7.5 | 12 | Lighting, sensors. |
| 1.0 | 10 | 10 | Dimensions, stop lamps |
| 1.5 | 15 | 8 | Passing beam headlamps |
| 2.5 | 20 | 6 | Fans, janitors |
| 4.0 | 30 | 4 | Audio systems, winches. |
When calculating, always lay a margin in the cross section of about 20-30%, especially if the wiring will be laid in conditions of poor ventilation or high temperature. Using a wire with a smaller cross section than required causes it to heat up, which increases resistance and further heats up the insulation, triggering a chain reaction up to a fire.
Wiring protection and installation methods
Even the best quality wire requires additional protection when laying in an aggressive environment of the car. Mechanical damage, vibration and friction against the metal edges of the body are the main enemies of electricians. For protection, corrugated tubes, cable channels and thermal shrink Cambricks are used, which prevent rubbing of the insulation and short circuit on the mass.
Particular attention should be paid to the places where wires pass through metal partitions. At these points, rubber bushings or thunderbolts are necessarily installed, protecting the cable from sharp edges. Corrugated tube (corrugated) must be made of polypropylene, resistant to temperature and oils, and have a fire safety certificate.
☑️ Checklist of safe installation
⚠️ Attention: Never leave the wires hanging or loose. Vibration when moving the car will lead to a rapid rubbing of the insulation against the body and a short circuit.
Mounting harnesses should be carried out with special plastic screeds or clips that provide reliable fixation without crushing the cable. Excessive tightening of the screed can deform the insulation and damage the veins, so it is important to control the force during installation. It is also not recommended to lay power and signal wires in one corrugated in order to avoid tips and interference.
Tools for working with automotive wiring
Quality installation is impossible without a specialized tool that provides reliable contact and safety of the veins. Conventional bogocreas or a knife often damage copper wires, reducing the effective cross-section of the wire at the cutting site. For professional work, a set is needed, including strippers for cleaning the insulation without damaging the veins and crimping mites (crimpers) for installing tips.
Stripper allows you to remove the insulation exactly to the desired length, without making notches on copper, which is critical for flexible multicore wires. Clutching mites ensure the formation of the correct tip profile, ensuring tight contact and no sparkling. The use of soldering is also allowed, but only with the use of special fluxes and provided that the connection is reliably fixed from vibrations.
Use only tinted copper tips. Conventional steel or aluminum terminals quickly oxidize and increase contact resistance.
To check the integrity of the chains and the correct installation, a digital multimeter is needed. With it, you can measure the voltage drop on the circuit section, check the presence of a short circuit on the mass and make sure the connection is correct. Regular diagnosis helps to identify potential problems before they lead to equipment failure.
Where to buy high-quality wires and what to look at
Purchase of car wires should be in specialized auto electric stores or official dealers of cable products, where they can provide quality certificates. Buying in the spontaneous markets or in questionable online stores is fraught with the purchase of counterfeit, where copper can be a copper-coated aluminum (CCA), and the insulation will not meet the declared characteristics.
When choosing a seller, pay attention to the presence of markings on the wire itself: the name of the manufacturer, the section, the type of insulation and the year of release should be clearly read. Certified products always has the appropriate documentation confirming compliance with GOST or international standards (ISO, SAE).
⚠️ Attention: Avoid wires marked "for household wiring" or without specifying the destination. They are not designed to be used in a vehicle and can cause a fire.
The price of quality materials cannot be too low, as copper and special polymer additives are expensive. Savings on wires can result in expensive repairs of burned wiring or elimination of the consequences of a fire. It is better to buy a reliable cable once than to constantly fix the malfunctions.
The safety of the car depends on the quality of each meter of wiring. Don’t skimp on cables and use only specialized automotive solutions.
Frequently Asked Questions (FAQ)
Can I use conventional household wires PVC or VDPE for the car?
It's not recommended. Insulation of household wires (PVC) is not resistant to oil, gasoline and low temperatures. In the cold, it sank and cracks, and when in contact with fuel softens, which leads to a short circuit and fire.
Which is better: single or multi-core?
For a car, a multi-core wire is better. It has high flexibility and resistance to vibrations. The single wire when shaking quickly breaks (metal fatigue), which leads to a break in the chain.
How to determine the cross-section of a wire without marking?
You can measure the diameter of one vein by a micrometer, calculate the cross-sectional area of one vein and multiply by their number. However, it is most accurate to use a table of correspondence of diameter and cross-section or caliber of wires.
Do I need to squirt the ends of the multi-core wire before crimping?
In an automotive electrician, tinting ends before squeezing into a terminal is not recommended, since when vibrating, the solder can crumble, and the contact will weaken. It is better to use special tips of NSHVI or squeeze pure copper.