Lighting Simulation — Master Technical Guide

1. Introduction

Designing a high-mast lighting system is never a theoretical exercise — it is a balance between optical precision, structural resilience, and real-world maintenance. Recent field projects in coastal and desert regions have shown that engineers often face conflicting requirements between glare control and wind load resistance. When luminaires are tilted for better coverage, their effective projected area (EPA) increases, magnifying structural stress. This whitepaper explores how Sunlurio HMS™ (High-Mast Simulation Suite) resolves those conflicts through integrated design simulation — aligning photometry, mechanics, and intelligent control in one workflow.

2. Application Scope

• Highways and interchanges (EN 13201-2 / CIE 115 Class ME1–ME3)
• Ports, container yards, and logistics terminals (EN 12464-2 / IES RP-8)
• Rail depots, airfields, and industrial maintenance zones
• Sports complexes and large urban plazas requiring vertical uniformity

Each environment brings its own constraint set — limited pole locations, high wind exposure, or strict glare limits — which HMS™ allows designers to quantify before fabrication begins.

3. Design Objectives

• Achieve target average illuminance (E_avg) and uniformity (U₀ ≥ 0.4) to ensure safe visibility — a crucial factor for driver visual adaptation at night.
• Minimize glare rating (GR ≤ 50), which directly affects visual comfort and adaptation time during high-contrast transitions.
• Verify mechanical stability under site-specific wind speeds per EN 1991-1-4; mast deflection directly influences optical alignment over time.
• Integrate smart dimming and control for adaptive energy management — reducing load during off-peak hours without losing compliance.
• Provide maintainability and safety through lowering systems, predictive maintenance, and runtime diagnostics.

4. Fundamental Optical and Photometric Principles

4.1 Illumination Geometry

E = Σ[(I_i × cos³θ_i) / h²]

In high-mast geometry, every degree of tilt changes the cosine³ θ term significantly. Field experience shows that a 5° aiming deviation can alter ground lux by more than 8 %, hence accurate aiming calibration is critical during commissioning.

4.2 Uniformity Ratio and Luminance

U₀ = E_min / E_avg ≥ 0.4  L = (E × ρ) / π

Uniformity defines perceived brightness continuity — vital in large truck yards where alternating bright and dark zones can fatigue drivers’ eyes.

5. Sunlurio HMS™ — Integrated Simulation Platform

Sunlurio HMS™ is more than a calculation engine; it is a digital workbench engineers use daily. In practice, designers import site geometry, simulate light spread, and even visualize mast deflection during typhoon scenarios. The software merges photometric analysis, structural stress mapping, and dimming control into one continuous loop.

5.1 Key Modules

Module	Purpose	Practical Output
Photometric Engine	Generates lux maps and glare analysis from IES/LDT imports	Uniformity charts, isolux diagrams
Structural Load Analyzer	Performs wind and stress simulation on pole geometry	Deflection (mm), stress (MPa), safety margin
Optic Aiming Simulator	Optimizes tilt and rotation for each luminaire ring	Aiming configuration (.HMA file)
Dimming Scheduler	Builds adaptive control profiles tied to traffic and weather data	.HDS schedule for IDS/HMS controllers

Engineers typically iterate through two to three HMS™ runs before reaching an optimum — reducing luminaire count by up to 15 % without losing uniformity.

5.2 Workflow Overview

1. Import DWG or GIS site model.
2. Select mast height, optics type, and luminaire quantity.
3. Run photometric simulation → adjust aiming → rerun.
4. Execute structural load test using built-in FEM solver.
5. Finalize dimming and control schedule.

6. Mechanical Design Parameters

Field experience suggests that even minor variations in wind classification change design outcomes dramatically. In coastal zones, thicker walls and wider bases are mandatory despite the same illuminance target.

• Height 20–45 m; base Ø 400–600 mm; wall 6–14 mm; steel S355 hot-dip galvanized.
• Wind force: F = 0.613 × C_d × A × V² (where C_d ≈ 1.2).
• Typical deflection limits: ≤ H / 400 to avoid beam displacement.

7. Optical Distribution and Arrangement

High-mast optics must reconcile beam overlap with glare suppression. Engineers often prefer mixed distributions — narrow (10°) for distant lanes, medium (30°) for mid-zones, and wide (60°) for apron areas — all verified in HMS™ through a composite lux overlay.

• 6–12 luminaires per ring, tilted 25–45° from nadir.
• Type II–III optics for linear roads, Type IV–V for open yards.
• Mounting: fixed headframe or motorized lowering ring with load sensors.

8. Electrical and Control Architecture

The electrical backbone is designed for resilience. Each mast integrates surge-protected circuits and IoT gateways that sync to the Sunlurio Cloud. During field calibration, sensors are fine-tuned to prevent overreaction to brief motion or vehicle flashes.

• Supply: 3-phase 400 V AC ±10 %, 50/60 Hz with 10 kV SPD.
• Drivers: DALI-2 / 1–10 V, PF ≥ 0.95, THD ≤ 10 %.
• Communication: LoRaWAN / NB-IoT secured MQTT link.
• Fail-safe: Auto-revert to last command if network loss > 60 s.

9. Intelligent Dimming and Automation

Intelligent dimming allows real-time adaptation to ambient and operational conditions. HMS™ integrates with Sunlurio IDS™ logic so that luminaires automatically shift output levels according to traffic sensors or astro-timers.

Time	Condition	Output %	Notes
18:30–22:00	Normal traffic	100	Full visibility
22:00–00:00	Moderate traffic	70	Automatic dimming
00:00–05:00	Low traffic	40	Energy-saving mode
Rain/Fog	Weather sensor	+20	Contrast enhancement

Annual verified saving: 48–55 % compared to static operation — confirmed through on-site power meter logs.

10. Simulation Case Study — Port Logistics Yard

Site: Coastal port yard (48 m × 160 m). 30 m mast with 8 × 400 W LED luminaires (Type V). Target E_avg ≈ 40 lx, U₀ ≥ 0.5, V_design = 45 m/s.

HMS™ Results:

• E_avg = 41.2 lx (±1.5 %)
• U₀ = 0.52 (±0.01)
• GR = 46 (measured 47 in field, Δ ≈ +2.1 %)
• Top deflection = 62 mm (limit ≤ 75 mm)
• Foundation moment = 92.4 kNm (SF = 1.35)

Measured values during on-site testing deviated less than 2.5 % from simulation predictions, confirming model fidelity under real wind and temperature conditions.

11. Maintenance and Reliability

• Lowering ring system rated 1.5× luminaire cluster load; motor equipped with anti-rollback brake.
• L70B10 ≥ 100 000 h at 25 °C; driver MTBF ≈ 80 000 h.
• Sunlurio Cloud monitors runtime hours, SPD events, and voltage fluctuations.
• Cleaning cycle: 12 months (urban) / 6 months (coastal) based on particulate index from HMS™ maintenance planner.

12. Environmental and Safety Compliance

• Wind Resistance Class up to 55 m/s per IEC 60598-2-3 Annex BB.
• Ingress Protection: IP66 (optical) / IP67 (driver box).
• Impact Resistance: IK09–IK10.
• Corrosion Protection: ISO 9227 ≥ 1000 h salt-spray.
• Dark-sky limit: ULR ≤ 1 % using full cut-off optics.

13. Deliverables and Documentation

• HMS™ Simulation Report (.HMR): illumination, uniformity, glare, wind load.
• Structural FEA chart (deflection & moment curve).
• Electrical and dimming schematics.
• Maintenance plan & predictive schedule report.
• Energy analytics summary from Sunlurio Cloud.

14. Summary

High-mast lighting sits at the intersection of civil, electrical, and optical engineering. Simulation makes precision achievable, but field variability — wind gusts, corrosion, voltage fluctuations — constantly tests theory. Our ongoing challenge remains balancing precision with practicality: ensuring every mast performs reliably under unpredictable real-world conditions while maintaining photometric integrity and energy efficiency. With the HMS™ digital twin workflow, Sunlurio continues refining this balance, turning each project into measurable progress for safer, smarter outdoor environments.

Author Introduction

Prepared by the Sunlurio Structural & Illumination Engineering Division. The division combines structural mechanics, photometric modeling, and IoT control expertise to deliver verified high-mast lighting systems across Africa, Southeast Asia, and the Middle East. Sunlurio HMS™ forms part of the company’s global simulation ecosystem linking design, analysis, and intelligent operation.