According to incomplete statistics, there were 52 electric vehicle fires in China from 2017 to the end of August 2019. Among them, 17 fires occurred during charging, accounting for 32.7%. This data warns us that EV charger safety protection is by no means a technical gimmick, but a rigid demand related to property, personal safety, and social responsibility.
As electric vehicles are rapidly gaining popularity, EV charging stations are the core infrastructure to ensure their rapid development. EV charger safety is directly related to the safety of users' lives and property, and the long-term stable operation of the EV charging equipment. TKT always puts product safety first. Today, I will first introduce you to the 16 important precision protection mechanisms. It builds multiple safety lines to protect your charging process.
EV chargers involve high voltage and high current transmission. If there is a lack of effective protection, it may cause dangers such as overvoltage, short circuit, and leakage. These dangers may damage the equipment at the least, or cause fire or electric shock accidents at the most.
Case reference: In 2021, a charger of a certain brand failed due to short-circuit protection, causing the cable to overheat and melt, and eventually causing the vehicle to catch fire. The accident investigation pointed out that the problem of EV charger safety is the lack of real-time current monitoring and a rapid circuit-breaking mechanism.
Operators typically install EV chargers outdoors. They are exposed to dust, extreme temperatures and other environments for a long time. If the protection level is insufficient, the internal circuit is susceptible to corrosion and cause failures.
Case reference: In a certain area, heavy rain infiltrated the EV charger, short-circuited it, and paralyzed multiple devices, exposing the hidden danger of a substandard IP protection level.
Improper plugging and unplugging, reverse battery connection and other misoperations may cause instantaneous high-voltage shock or short circuit, threatening user safety.
As a leading company in the field of new energy charging, TKT EV charger safety uses the dual-engine technology of "active defense + intelligent monitoring" to nip safety hazards in the bud.
1.1, Overvoltage/Undervoltage Protection: real-time monitoring of grid voltage, immediate shutdown when exceeding the AC 380V±15% range to avoid voltage fluctuations damaging the EV charging equipment.
1.2, Phase Loss and Surge Protection: detect the integrity of the three-phase input, and suppress grid spikes through the SPD module to protect the internal circuit from impact.
1.3, Overcurrent and Short-circuit Protection: intelligent current control and vehicle BMS work together to dynamically match the charging current, and cut off the output within 0.1 seconds when the current exceeds the limit to eliminate the risk of fire.
2.1, Anti-reverse connection protection: Automatically identify the battery polarity to avoid short circuits caused by misconnection (a user once caused the battery to smoke due to reverse connection, and this function of TKT can completely avoid it).
2.2, Mechanical interlock design and plug-in detection: Inserting the charging interface automatically triggers the electronic lock, and the system prohibits power supply if the lock hasn’t engaged; the plug-in detection sensor detects displacements as small as 0.1 mm to prevent live plug-ins.
2.3, IP54 protection: Sealed design and dustproof and waterproof structure, no fear of harsh environments such as heavy rain and sandstorms.
3.1, Dual over-temperature protection: Real-time monitoring of the temperature of the charging plug and core components, automatic power reduction or shutdown when over-temperature (for example, a competitor's module burned due to insufficient heat dissipation, TKT did not have a similar accident).
3.2, Cable Overload Protection: Real-time detection of plug temperature to prevent the cable from overheating and melting, eliminating fire hazards.
4.1, Leakage Protection: When leakage current on the AC/DC side exceeds 30 mA, the charger cuts power within 0.04 seconds—far exceeding the industry standard.
4.2, Emergency Stop Button and Self-check Mechanism: The emergency stop button supports cutting off the main circuit within 0.3 seconds to deal with emergencies and provide the ultimate guarantee for safety. With the daily self-check function, the failure rate is reduced by 83%.
| Serial number | Protection Type | Protection Name | EV Charger Safety Protection Definition |
| 1 | Input side protection | Overvoltage/undervoltage protection | Monitor the input voltage (our charger is detected by the charging module and judged by the charging control system). When the voltage exceeds the rated range (such as AC 380V±15%), stop charging to prevent equipment damage. |
| 2 | Input side protection | Phase loss protection | Detect whether any phase of the three-phase input of the AC input is missing (our charger is detected by the charging module and judged by the charging control system) to avoid damage to internal components. |
| 3 | Input side protection | Surge protection | The surge peak from the power grid is suppressed by the lightning protection module SPD to protect the internal circuit. |
| 4 | Output side protection | Overcurrent protection | Real-time monitoring of output current. If it exceeds the set value of the vehicle BMS limit (the charging control system collects data and analyzes and judges, and issues action instructions), the output is immediately cut off. |
| 5 | Output side protection | Short circuit protection | Detect output short circuit (the charging control system collects signals and analyzes and judges, and issues action instructions), and quickly disconnect the output circuit. |
| 6 | Output side protection | Anti-reverse connection protection | Prevent the positive and negative poles of the vehicle battery from being connected in reverse (the charging control system collects signals and analyzes and judges), avoiding the risk of short circuit. |
| 7 | Output side protection | Overvoltage/undervoltage protection | The charging control system communicates with the vehicle BMS in real time to ensure that the charging voltage does not exceed the battery's allowable range. |
| 8 | Output side protection | Overtemperature protection | The charging interface temperature is measured by the temperature sensor, and the power is reduced or shut down when the temperature exceeds the limit. |
| 9 | Equipment self-protection | Overheat protection | Monitor the temperature of the internal components of the EV charger (such as the charging control system, charging module) to prevent high temperature damage. |
| 10 | Equipment self-protection | Dust and water resistant (IP rating) | The housing design complies with the IP54 standard to prevent foreign matter and moisture from entering, ensuring that the EV charger can operate normally in harsh outdoor environments. |
| 11 | Mechanical and connection protection | Charging interface plug-in detection | Stop power supply when not fully inserted or accidentally disconnected |
| 12 | Mechanical and connection protection | Electronic lock failure | Charging is prohibited when the interface lock is not locked normally |
| 13 | Mechanical and connection protection | Cable overload protection | The charging control system monitors the temperature of the charging interface to prevent overheating and melting |
| 14 | System-level protection | Residual current detector (RCD) | Detects leakage current on the DC or AC side and cuts off the power supply when it exceeds the set value |
| 15 | System-level protection | Ground fault protection | Monitors ground loop anomalies to avoid the risk of electric shock |
| 16 | System-level protection | Emergency stop protection | Directly cut off the power supply through the hardware button to deal with emergencies |
Case 1: In 2022, a charger in a parking lot caused an electric shock to a user due to a grounding fault. TKT's grounding fault protection can monitor and cut off abnormal circuits in real time, completely avoiding such risks.
Case 2: A charging interface of a certain brand was not equipped with a temperature sensor. After long-term use, the interface head melted and caused a fire. TKT's cable overload protection can provide early warning and shutdown.
These accidents prove that "safety is no small matter", and TKT EV charger safety kills the risk in the bud through full-link closed-loop protection.
EV charger safety is not only a technical proposition, but also a reflection of corporate values. TKT always believes that safety is the lifeline of charging equipment. We not only follow international standards, but also use protection designs that exceed industry standards to build a "zero hidden danger" charging experience for users. Choosing TKT means choosing a respect for life and a commitment to quality.
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