This document defines the mechanical, thermal, and environmental design requirements for a fanless outdoor IP Camera, optimized for direct sunlight exposure, sealed enclosure, and long-term industrial deployment.
This specification is intended for:
- Mechanical design vendors
- Enclosure / die-casting suppliers
- Thermal verification and DVT/PVT stages
| Item | Target |
|---|---|
| Cooling method | Fully passive (fanless) |
| Enclosure rating | IP66 / IP67 |
| Ambient temperature | -20 °C to +60 °C |
| Solar radiation | ≥ 1000 W/m² |
| Internal temperature rise | ≤ +25 °C over ambient |
| Expected lifetime | ≥ 5 years outdoor |
- Main housing: Structural + primary heat dissipation body
- Sun shield: Solar radiation blocking only
- Lens window module: Optical + environmental sealing
- Mounting bracket: Mechanical support (thermally isolated)
| Component | Thermal Role |
|---|---|
| Aluminum housing | Heat sink |
| Sun shield | Radiation barrier |
| Air gap | Thermal resistance |
| Mount bracket | Structural only |
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Material: Aluminum alloy (ADC12 / A6063)
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Wall thickness:
- General: ≥ 2.5 mm
- Top surface: ≥ 3.0 mm
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Manufacturing:
- Die casting or extrusion + CNC
- Outdoor-grade powder coating
- Color: Light gray / white
- Emissivity: ≥ 0.85
- UV resistance: ≥ 5 years
- Housing shall act as the only external heat dissipation path
- External geometry shall promote natural convection
- No thermal interface allowed between housing and sun shield
| Module | Typical Power |
|---|---|
| SoC / ISP | 2–4 W |
| Image Sensor | 0.5–1 W |
| IR LED array | 2–6 W (peak) |
| Power regulation | 0.5–1 W |
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SoC and power ICs must be thermally coupled to housing
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Thermal interface material:
- Thermal pad: 3–6 W/m·K
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PCB shall include thermal vias under SoC
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IR LED module must:
- Use independent aluminum heat spreader
- Avoid thermal coupling to image sensor
- Block direct solar radiation
- Must not participate in heat dissipation
- Must not conduct heat into housing
| Material | Recommendation |
|---|---|
| ASA / UV PC | Preferred |
| FRP | Acceptable |
| Thin aluminum | Allowed with isolation only |
- Color: White / light gray
- Finish: Matte
- Optional: IR-reflective coating
- No metal-to-metal contact allowed
- Sun shield mounting shall maximize thermal resistance
| Parameter | Requirement |
|---|---|
| Material | POM / Nylon / PEEK / FR4 |
| Quantity | 3–4 points |
| Height | 20–30 mm |
| Contact area | Minimized |
- Preferred: Plastic screws
- Alternative: Stainless screws + insulating sleeves
- Insulating washers required on both sides
- Minimum gap: 15 mm
- Recommended gap: 20–30 mm
- Gap must be open to ambient air
- No sealing foam or thermal pads allowed
Purpose:
- Reduce conductive heat transfer
- Reduce radiative coupling
- Prevent hot air accumulation
- Optical glass or tempered glass
- Anti-UV, anti-IR coating recommended
- Dual O-ring preferred
- Mechanical compression sealing
- Adhesive sealing as secondary protection only
- Sun shield must extend forward (visor style)
- Direct solar exposure to lens is prohibited
- Internal pressure equalization membrane (ePTFE)
- Optional desiccant for initial moisture control
- Stainless fasteners (A2/A4)
- Galvanic isolation between dissimilar metals
- Target is dust tolerance, not zero dust ingress
- Design shall ensure thermal performance degradation ≤ 15% over 5 years
- No active cleaning mechanisms allowed
- Fin spacing: ≥ 6–8 mm
- Fin height: ≤ 10–12 mm
- Fin orientation: Vertical, downward preferred
- Sharp corners prohibited (dust bridging risk)
- No horizontal flat surfaces > 10 mm width
- All external surfaces shall have ≥ 15° inclination
- Drain paths must be continuous (no dust traps)
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Natural rain wash capability required
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Drip edges required on:
- Sun shield perimeter
- Housing top edges
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No enclosed cavities open upward
| Area | Requirement |
|---|---|
| Housing | Outdoor powder coating, low surface energy |
| Sun shield | Matte, anti‑static surface |
| Lens window | Hydrophobic + oleophobic coating |
Anti‑static or dust‑repellent coatings are recommended where feasible.
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Sun shield must be:
- Open‑sided
- Non‑enclosed
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Minimum clearance to housing: 20–30 mm
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No U‑shaped or box‑type geometries allowed
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ePTFE vent membrane required
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Vent must be:
- IP66/IP67 rated
- Dust ingress compliant (ISO 20653)
- Oleophobic for polluted environments
Recommended validation tests:
- Dust exposure + thermal cycling test (IEC 60068‑2‑68)
- Water spray cleaning simulation
- Post‑test thermal resistance measurement
Acceptance criteria:
- No structural dust accumulation blocking convection paths
- Thermal resistance increase ≤ 15%
- Direct metal mounting of sun shield to housing
- Using sun shield as a heat sink
- Dark-colored external surfaces
- Enclosed sun shield trapping hot air
In outdoor IP camera design, solar heat rejection is more critical than internal heat dissipation.
The sun shield is a radiation barrier, not a thermal component.
- Document Type: Engineering Design Specification
- Product Class: Outdoor IP Camera
- Revision: Draft v1.1