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Safety that leaves nothing to chance
From cell to system, every layer is designed to prevent, detect and contain. Your energy, protected at every level.
Banner: Designed to avoid single points of failure.
Button: Talk to a FOX ESS expert
The reassuring benchmarks
Benchmark | What it means |
Up to IP66 | Protected against dust and water jets, built to live outdoors all year (depending on model) |
Extended temperature range | Reliable from winter cold to summer heat, with automatic battery heating in extreme cold (depending on model) |
Seamless switch | Off-grid mode takes over seamlessly (depending on model) |
Tier-1 LiFePO₄ | A chemistry known for its stability and longevity |
Five lines of defense, from cell to system
1. It all starts in the cell. Tier-1 LiFePO₄ cells offer superior stability and a longer lifespan.
2. A system that watches over itself. Sensors measure temperature, voltage and current in real time: any drift is spotted before it becomes a problem.
3. Hazards cut off before they exist. Depending on the product, several protections work together:
• The arc detector (AFCI) spots dangerous sparks and cuts power before any fire can start.
• The surge protector (SPD) and varistor (MOV) absorb voltage surges.
• The fuse cuts power within milliseconds.
• A single DC switch shuts the whole system down.
4. Fire, anticipated at the source. Depending on the model, module-level protection detects and prevents thermal runaway, with a fire-suppression aerosol built into the battery. A pressure relief valve, a breather vent and relays with a backup design keep the system reliable even if one relay fails.
5. Built for every climate. Die-cast aluminum housing, highly rigid, protection up to IP66 and built-in cooling to keep the system stable (depending on model).
Every risk has its answer
The risk | Our answer |
Overheating | Module-level protection, sensors, LiFePO₄ cells |
Electric arc | AFCI: immediate detection and shutoff |
Lightning and surges | SPD and MOV |
Short circuit | Fuse and relays with a backup design |
Overpressure | Pressure relief valve and breather vent |
Weather | Die-cast aluminum, protection up to IP66, extended temperature range |
Emergency | A single DC switch to cut everything |
Exact protections depend on the product: talk to our teams.
A three-level protection architecture
Safety is not added at the end of the design: it is built into every scale of the system, from the cell to the complete installation. If one level is challenged, the next takes over.
Level | Protection elements | Technical role |
Cell | LiFePO₄ (lithium iron phosphate) chemistry, selected Tier-1 cells | Intrinsic thermal and chemical stability, strong resistance to thermal runaway |
Battery module | Temperature, voltage and current sensors; module-level fire protection (built-in fire-suppression aerosol); pressure relief valve and vent, depending on the model | Early detection of drift, containment and limitation of any thermal event |
System | DC and AC electrical protections, relays with backup design, aluminium housing, remote monitoring | Fault interruption, isolation, protection of the whole unit and continuous follow-up |
Electrical protections in detail
Each protection answers a specific fault. Their combination, which varies by range, covers the main risk sources of a solar-plus-storage installation.
Protection | How it works | Risk prevented |
AFCI (arc-fault detection) | Continuously analyses the DC current signature and cuts off on a series or parallel arc | Fire start caused by a faulty connector or cable |
SPD + MOV (surge protector and varistor) | Clamps transient overvoltages by diverting them to earth | Damage from lightning or grid disturbances |
Fuse | Opens the circuit when current exceeds the rated value | Overcurrent and short circuit |
DC switch | Physically isolates the PV array or the battery | Safe intervention, maintenance |
Relays with backup design | Redundant disconnection function | Failure of a switching component |
Multiple sensors (temperature, voltage, current) | Monitor values in real time and trigger a battery management response | Thermal drift, overcharge, deep discharge |
Depending on the model, some protections may differ or be supplemented. Each product's datasheet prevails.
Thermal management and mechanical enclosure
Temperature is the first factor in a battery's lifespan and safety. Our approach rests on three axes.
• Stable chemistry: LiFePO₄ offers higher thermal stability than many other lithium-ion chemistries.
• Temperature control: distributed sensors, an extended operating range and, depending on the model, automatic battery heating in cold weather.
• Controlled venting: pressure relief valve and breather vent, depending on the model, to handle pressure variation without compromising housing sealing.
The enclosure is built to last: die-cast aluminium housing, protection rating up to IP66 (fully dust-tight, resistant to powerful water jets) for outdoor installation.
International standards, not promises
Our products are designed to meet the applicable international safety standards, notably the IEC/EN 62109 series (safety of converters for photovoltaic systems) and IEC/EN 62477-1 (safety of power electronic converters), under the Low Voltage Directive. Exact references depend on each product: contact us.
Installed safely, monitored continuously
• Designed to make installation easier. Depending on the product, precise height adjustment reduces lifting effort and risks during installation.
• FoxCloud 2.0 keeps an eye on everything. One-press diagnosis from the app, energy flow refreshed every 5 seconds, system status available at any time.
Remote monitoring and diagnostics
A safe installation is one you can monitor. With FoxCloud 2.0, installers and users have actionable data.
• Real-time energy flow, refreshed every 5 seconds
• Plant data: production, consumption, battery status
• One-press diagnosis to quickly identify an anomaly
• Alerts and history to anticipate rather than endure
• Smart control: compatibility with virtual power plant (VPP) uses, depending on the market
Exact features may vary by product and platform version.
Your questions, our answers
What if a cell heats up? Sensors spot the drift and, depending on the model, module-level protection prevents thermal runaway, backed by a built-in fire-suppression aerosol and the pressure relief valve.
Outdoors, all year round? Our products are designed for outdoor use: protection up to IP66, extended temperature range and, for batteries, automatic heating in extreme cold (depending on model).
What if the grid goes down? Systems with an off-grid mode switch over seamlessly.
What does IP66 mean? The first digit (6) means fully dust-tight; the second (6) means resistance to powerful water jets. The rating applies to the specific equipment: refer to the product datasheet.
Why LiFePO₄ chemistry? It offers a stable crystal structure, good thermal tolerance and a high cycle life, a recognised choice for residential storage.
What is AFCI protection for? An electric arc can form on a degraded DC connection. AFCI detection recognises its signature and cuts the circuit before it becomes a risk.
Where can I find the standards references for a specific product? In its datasheet and certificates, available on request from our team.
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Homeowner, installer or insurer: our teams answer all your safety questions. Button: Contact FOX ESS France
Exact protections depend on the product: talk to our teams.