Charging Workshop Hydrogen Detection Solution

With the rapid popularization of new energy vehicles, electric forklifts, and electric buses, centralized charging workshops have become standard infrastructure in logistics parks, factories, bus depots, and 4S store after-sales markets. During charging, battery packs (especially lead-acid batteries and some older lithium batteries) can generate hydrogen through water electrolysis under overcharge, short circuit, or fault conditions. Hydrogen is colorless, odorless, extremely light (about 1/14 of air density), and has a wide explosive range (4%–75%). If it accumulates in poorly ventilated workshops, it significantly increases fire and explosion risks.

Nexisense addresses hydrogen safety concerns in charging locations with a complete solution centered on the SGA-500 series online hydrogen detectors, combined with the SGA-800 alarm controller, helping enterprises effectively control hydrogen leakage risks and protect personnel and equipment.

Hydrogen Generation and Risk Characteristics in Charging Workshops

During charging, hydrogen mainly originates from:

• Electrolysis during overcharging of lead-acid batteries

• Minor hydrogen generation in some lithium batteries during early thermal runaway or internal short circuits

• Abnormal gas evolution due to aging battery packs, poor connections, or charger faults

Hydrogen’s most notable physical characteristic is its extremely low density. Once leaked, it rises rapidly and accumulates near roofs, beams, and ceilings, forming explosive gas layers. Therefore, hydrogen detectors must be installed at the highest points, opposite to other gases like chlorine or hydrogen sulfide.

Additionally, charging workshops often have frequent personnel movements (forklift operators, maintenance staff, and charging managers). Therefore, monitoring must consider both the lower explosive limit (LEL) and toxicity limits (TLV) to ensure personnel awareness of potential hazards before entry.

Key Advantages of Nexisense SGA-500 Series Online Hydrogen Detectors

The SGA-500 series is industrial-grade and features:

• Explosion-proof certification for Zone 1 and Zone 2 hazardous areas

• CE and RoHS certifications, with high international recognition

• Durable aluminum alloy housing suitable for humid and dusty environments

• Wide voltage supply (DC 12–30V) for complex onsite power conditions

• Dual output signals: 4–20mA analog + RS485 digital, supporting long-distance transmission

• High compatibility with over 90% of mainstream PLC, DCS, gas alarm controllers, and DDC systems

• Three sampling methods: natural diffusion, pump suction, and closed-pipe sampling

• Imported hydrogen sensors with full-range temperature and humidity compensation, automatic zero calibration to reduce false alarms

• Large LCD display showing gas type, unit, and concentration in real time

• Three-color indicator lights (green-normal, yellow-fault, red-alarm)

• Integrated high-decibel audible/visual alarm (>85dB)

• Optional relay outputs for fan, solenoid valve, or sprinkler linkage

• Infrared remote parameter adjustment for zeroing, high/low alarm setting, and calibration without opening the cover

• Triple protection design: overload, misoperation, and lightning protection

  
  

Scientific Installation Principles for Hydrogen Detectors

Due to hydrogen’s low density, Nexisense strongly recommends:

• Install detectors at the highest points: roof, ceiling, under beams, near exhaust vents

• Set monitoring points every 80–150㎡, adjustable based on ventilation and parking density

• Avoid ventilation dead zones, directly under fans, or near fresh air inlets

• Prioritize coverage above charging piles, battery concentration areas, and maintenance pathways

Building Multi-Workshop Hydrogen Alarm and Linkage Systems

For sites with multiple charging stations or independent workshops, a single detector cannot provide centralized management. The SGA-800 alarm controller can integrate multiple SGA-500 detectors to form a regional hydrogen monitoring network:

• Real-time display of hydrogen concentration, alarm status, and trend curves for each monitoring point

• Multi-level alarm settings (pre-warning, alarm, interlock)

• Area linkage: alarms in one workshop can trigger local fans or notify the central control room

• Remote data transmission via RS485 or Ethernet to security platforms or energy management systems

• Historical records and reports for auditing and accountability

Typical Applications and Practical Value

• New energy vehicle centralized charging stations (logistics parks, taxi depots, bus depots)

• Electric forklift charging rooms (large warehouses, manufacturing plants)

• Electric sanitation or sightseeing vehicle charging areas

• Battery manufacturing charging test zones

• 4S store after-sales new energy vehicle charging areas

Users report that installing the Nexisense hydrogen detection system:

• Effectively prevents safety hazards caused by hydrogen accumulation

• Reduces risks during unmanned periods at night

• Significantly improves ventilation efficiency through fan linkage, reducing energy consumption

• Enhances employee confidence in charging environment safety

  
  

FAQ

1. Why must hydrogen be monitored in charging workshops? Lead-acid and some lithium batteries generate hydrogen during charging. Its wide explosive range (4%-75%) makes closed spaces highly risky. Unmonitored hydrogen is a major cause of fire accidents.

2. Why install detectors at high points? Hydrogen density is only 1/14 of air; it rises and accumulates at ceilings. High installation ensures early detection and fast alarm response.

3. What measurement range should detectors use? Considering personnel exposure, recommended range is 0–1000 ppm (or 0–2000 ppm); for explosion risk only, 0–100%LEL. Many scenarios prefer dual-range 0–2000 ppm.

4. Does SGA-500 integrate with existing security systems? Supports 4–20mA and RS485 Modbus RTU outputs for connection to most PLCs, DCS, security platforms, or third-party gas alarms.

5. Is hydrogen detection necessary if ventilation is good? Yes. Even with good ventilation, local faults or charger anomalies may rapidly raise hydrogen levels. Detectors act as the last line of safety.

6. What happens after an alarm? Relay output or controller linkage can start fans, open vents, cut charging power, trigger audible/visual alarms, and even activate sprinklers.

7. How often should equipment be calibrated? Recommended every 6–12 months using standard gas. Built-in zero-tracking extends calibration cycle and reduces false alarms.

8. How long is the ROI for hydrogen detection systems? Avoiding a single major accident can save millions; most users see ROI within 1–3 years through risk reduction, insurance benefits, and operational confidence.

Conclusion

Hydrogen safety in charging workshops affects personnel, equipment, and operational continuity. The SGA-500 series online hydrogen detectors, with explosion-proof certification, stable performance, flexible outputs, and linkage capabilities, are trusted in many new energy vehicle charging stations, forklift charging rooms, and bus depots. Combined with SGA-800 alarm controllers, a multi-point, centralized, and linked hydrogen safety management system can be quickly established. Managers are advised to assess hydrogen risks early based on workshop size, parking density, ventilation, and personnel activity, and adopt professional gas detection systems. Safety is not a cost but a prerequisite for sustainable development.