Static power consumption detection method for automobile circuit

Abstract

The invention discloses an automobile circuit static power consumption detection method, belongs to the technical field of automobile electrical detection, and aims to solve the problems of complexity, tedious operation and high cost of existing detection equipment. According to the technical scheme, alligator forceps are used for clamping a fuse box positive terminal, and a needle-shaped meter pen is attached to the single end face of the rear end of a fuse to form a single-side double-point structure; the voltage drop delta U is measured through a millivolt gear of a universal meter with the precision larger than or equal to 0.1%; and pre-storing an equivalent total resistance reference value 0.0075 ohm, substituting the equivalent total resistance reference value 0.0075 ohm into a formula to calculate a quiescent current, and judging electric leakage of downstream equipment or abnormal power consumption of a battery in combination with a vehicle standard threshold (for example, a new energy vehicle is less than or equal to 50mA). The method does not need special equipment, only needs a universal meter, a crocodile clamp and a meter pen, is low in cost, is simple and convenient to operate, consumes less than or equal to 2 minutes for one time, is suitable for a narrow space and multiple vehicle types, is small in error, can accurately distinguish equipment leakage and battery faults, and improves the detection efficiency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of automotive electrical testing technology, and more particularly to a method for quickly and accurately detecting static power consumption in automotive circuits and determining the health status of low-voltage batteries. This method utilizes simple tools to measure the voltage drop between the fuse box terminal and the fuse via single-sided contact measurement. It is suitable for scenarios such as auto repair shops and 4S stores where fault diagnosis of automotive circuits and low-voltage battery health assessment are performed. Background Technology

[0002] Abnormal static power consumption and low-voltage battery health issues are common problems encountered during vehicle use. Traditional methods for testing static power consumption in automotive circuits often have several drawbacks. On the one hand, existing testing equipment is usually quite complex, relying heavily on dedicated, highly integrated testing devices. These devices are not only expensive but also bulky and inconvenient to carry, making them extremely difficult to operate in actual automotive repair scenarios, especially in confined spaces. On the other hand, the testing process is cumbersome, potentially requiring specialized technicians to perform complex operations, including disassembling parts of the vehicle and connecting various testing circuits. This is not only time-consuming but may also cause additional damage to the vehicle's electrical system due to improper handling.

[0003] Furthermore, traditional methods struggle to accurately distinguish whether abnormal battery power consumption is caused by the vehicle's electrical modules or a problem with the battery itself when assessing its health. This leads to inefficiency for repair personnel during troubleshooting, hindering their ability to quickly and accurately pinpoint the root cause of the problem. Consequently, it impacts the overall efficiency and quality of automotive repairs, increasing repair costs and customer wait times. Therefore, developing a simple and cost-effective method for detecting static power consumption in automotive circuits is urgently needed. Summary of the Invention

[0004] Single-sided contact connection: The operator holds alligator pliers in their left hand, clamping them onto the conductive surface of the positive terminal of the fuse box. With their right hand, they hold a needle-shaped test probe, aligning it with the single end face of the fuse's rear end, thus forming a single-sided, two-point physical separation structure. The alligator pliers use toothed copper contact surfaces with a specially designed diameter to perfectly match the positive terminal of the fuse box, effectively reducing contact resistance and facilitating quick, one-handed clamping operation, improving testing efficiency. The needle of the test probe precisely matches the rear end face of the fuse, using copper (or gold-plated) material with a contact resistance ≤0.001Ω, ensuring good conductivity and stable signal transmission during measurement.

[0005] Millivolt-level differential voltage measurement: Select a general-purpose multimeter with an accuracy ≥0.1%, set it to the millivolt range, and then connect it in parallel between the alligator clips and the needle probes. The multimeter has high resolution and can read the real-time voltage drop signal ΔU with a resolution ≤1mV, enabling precise measurement of minute voltage changes and providing reliable data for subsequent accurate current calculations.

[0006] Rapid calculation using fixed resistance: The relevant circuit is measured beforehand using the four-wire method to obtain and store the reference value R of the equivalent total resistance of the fuse under test. aeq = 0.0075Ω. This equivalent total resistance includes the fuse body resistance and contact resistance, and is obtained by calibrating fuses of the same specification (e.g., 10A) more than three times at 25°C and taking the average value. During the testing process, the voltage drop signal ΔU read is directly substituted into the formula. The static current I can then be calculated quickly.

[0007] Determining leakage and battery health: The calculated current I is compared with a preset threshold, which is determined based on a pre-defined standard current data table for different vehicle models (e.g., for new energy vehicles, the standard is total current consumption I ≤ 50mA). If the calculated current I exceeds the preset threshold, it is determined that there is a leakage fault in the downstream equipment. Simultaneously, by continuously monitoring current fluctuations in conjunction with the rated capacity of the low-voltage battery, the source of abnormal battery power consumption can be determined, clarifying whether the abnormal power consumption is caused by the vehicle's electrical module or a problem with the battery itself. The pre-defined standard current data table for the vehicle model is obtained by recording the standard current values ​​of multiple corresponding fuses in the fuse box of the same vehicle model under conditions of static power consumption standards, a service life of less than one year, and an ambient temperature of 25℃, providing a reliable basis for accurate judgment. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the measurement device connection for the static power consumption detection method of automotive circuits, used to illustrate the single-sided contact measurement structure and circuit connection relationship of the present invention.

Claims

1. The independent claim 1 provides a method for detecting static power consumption in automotive circuits, characterized in that, Includes the following steps: Using a single-sided contact connection: Hold the alligator pliers in your left hand to clamp the conductive surface of the positive terminal of the fuse box, and hold the needle-shaped test probe in your right hand to adhere to the single end face of the rear of the fuse, forming a single-sided double-point physical separation structure; To perform millivolt-level differential voltage measurement: Use a general-purpose multimeter with an accuracy of ≥0.1% in the millivolt range, connect alligator clips and test leads in parallel, and read the real-time voltage drop signal ΔU with a resolution of ≤1mV; Rapid calculation using a fixed resistor: using a pre-stored equivalent total resistance reference value R. aeq =0.0075Ω, substitute into the formula Calculate the quiescent current I; Determining leakage current and battery health: Compare the calculated current I with a preset threshold (total current consumption I≤50mA, standard for new energy vehicles, based on the standard current data table of the vehicle model). If it exceeds the threshold, it is determined to be a leakage current fault in downstream equipment. Combined with the rated capacity of the low-voltage battery, the source of abnormal power consumption of the battery is determined by monitoring current fluctuations.

2. The method for detecting static power consumption of automotive circuits according to claim 1, characterized in that: The alligator pliers have toothed copper contact surfaces with a diameter adapted to the terminals to reduce contact resistance and support quick clamping with one hand; the needle-shaped test probes match the rear face of the fuse and are made of gold-plated copper with a contact resistance ≤0.001Ω.

3. The method for detecting static power consumption of automotive circuits according to claim 1, characterized in that: The general-purpose multimeter is in the millivolt range, with a display of four and a half digits, and an equivalent resistance R. aeq =0.0075Ω, calculate the current value I according to the formula.

4. The method for detecting static power consumption of automotive circuits according to claim 1, characterized in that: The equivalent total resistance reference value Raeq = 0.0075Ω is obtained through four-wire calibration, covering the fuse body resistance and contact resistance. It is obtained by averaging the values ​​of more than three calibrations of fuses of the same specification (e.g., 10A) at 25℃, and can be directly used without real-time calibration.

5. The method for detecting static power consumption of automotive circuits according to claim 1, characterized in that: The vehicle model pre-made standard current data table is a record of the standard current of multiple corresponding fuses in the fuse box of the same vehicle model, which meets the static power consumption standard and is used for less than one year under an ambient temperature of 25°C.

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