High Mast LED Retrofit Guide: Replacing Metal Halide and HPS Systems

Quick Answer

High mast LED retrofit should not be handled as a simple wattage swap.

A 1000W metal halide, 1500W HID or HPS high mast light cannot be reliably replaced by choosing a fixed LED equivalent from a generic chart. The correct LED retrofit solution depends on the existing system input power, current lighting performance, pole height, headframe layout, luminaire optics, fixture weight, effective projected area, wiring, controls, surge protection and DIALux or equivalent photometric verification.

A practical retrofit process should follow this sequence:

survey → measure → specify → check structure and electrical system → simulate → trial → commission → verify savings

For early screening, lower LED input power may often be possible because LED luminaires can deliver more useful light and better optical control than older HID systems. However, final selection must be based on measured conditions, LED photometric files, maintained lighting requirements and compatibility with the existing high mast system.

The goal is not only to reduce wattage. The goal is to maintain or improve lighting performance while reducing energy use, maintenance risk and long-term operating cost. This is consistent with retrofit research and guidance that treats LED upgrades as performance, controls, maintenance and lifecycle-cost decisions rather than simple lamp-wattage substitutions.

Project Review Summary

Item	Project Review Point
Main Topic	High mast LED retrofit for metal halide, HPS and HID systems
Main Question	How should existing high mast lights be replaced with LED safely and accurately?
Best-Fit Projects	Ports, logistics yards, industrial yards, highways, toll areas, airports, mining yards, parking areas and municipal infrastructure
Main Retrofit Risk	Treating HID-to-LED replacement as a simple wattage-equivalent chart
Required Review	Existing system survey, current lighting measurement, LED photometry, structure, electrical system, controls and DIALux verification
Key Compatibility Items	Pole height, fixture quantity, headframe, lowering system, fixture weight, EPA, wiring, driver behavior, SPD and control protocol
Typical Project Stage	Retrofit audit, RFQ preparation, energy-saving review, DIALux comparison, BOQ update and upgrade proposal
Typical Deliverables	Retrofit review, IES/LDT files, DIALux comparison, aiming schedule, electrical/mechanical coordination inputs and BOQ

Why High Mast LED Retrofit Is Not a Simple Wattage Swap

Many retrofit discussions begin with a simple question:

What LED wattage replaces a 1000W metal halide high mast light?

This question is understandable, but it is incomplete.

A HID lamp wattage is not the same as total system input power. The actual operating load may include ballast losses, aging lamps, deteriorated reflectors, dirty lenses, voltage variation and outdated control systems.

A LED high mast luminaire also differs from HID in several important ways:

• LED light is directional.
• HID lamps often rely on reflector systems.
• LED luminaires use drivers instead of ballasts.
• LED fixture weight and projected area may differ.
• LED optics may change beam spread and aiming behavior.
• LED can support dimming and smart controls.
• LED color, CRI and visibility may be different.
• LED drivers may create different inrush-current behavior.
• LED surge protection requirements may differ from the old system.

Because of these differences, a simple equation such as “1000W metal halide = 400W LED” can create technical risk.

It may lead to:

• Insufficient maintained illuminance.
• Dark zones between high mast poles.
• Excessive glare.
• Uneven lighting.
• Wrong beam distribution.
• Headframe overload.
• Incompatible brackets.
• Electrical or driver problems.
• Incorrect BOQ.
• Poor acceptance during commissioning.

A retrofit project should therefore start with the existing system and the required post-retrofit performance, not with a universal replacement wattage.

Metal Halide, HPS and LED: What Changes in Retrofit Projects

High mast retrofit projects commonly involve replacing metal halide, high-pressure sodium or other HID luminaires with LED.

Each light source type has different behavior.

System Type	Typical Retrofit Issue	LED Review Point
Metal halide	Lumen depreciation, ballast losses, lamp aging, color shift	Check existing measured level, LED optics, CCT, CRI and maintained performance
HPS	Lower color rendering, different visual appearance, old optics	Review visibility, CCT, CRI, glare and target-zone lighting
HID high mast	Larger old fixtures, reflector-based distribution, ballast system	Review fixture weight, EPA, headframe, wiring and driver compatibility
Existing LED system	Early-generation LED efficiency or optical limitations	Compare photometry, driver condition, controls and actual performance

LED retrofit can reduce energy and maintenance cost, but it also changes the optical system.

That change is valuable only when it is controlled.

A well-selected LED luminaire may improve useful light distribution and visibility. A poorly selected LED luminaire may create hot spots, dark zones or glare even if the wattage looks reasonable.

Why HID Wattage Equivalence Can Be Misleading

HID-to-LED equivalence charts can help shortlist LED products, but they should be used only as preliminary screening tools. They cannot approve a high mast retrofit.

HID Lamp Wattage Is Not Total System Power

A 1000W HID lamp may not consume exactly 1000W at the system level. The ballast, control gear and operating condition affect actual input power.

A retrofit energy calculation should use actual system watts where possible, not only nominal lamp wattage.

Existing Light Output May Be Degraded

Older HID systems may already be operating below original performance because of:

• Lamp lumen depreciation.
• Dirty lenses.
• Reflector aging.
• Ballast condition.
• Incorrect lamp replacement.
• Corrosion.
• Water ingress.
• Misalignment.
• Partial failures.

If the existing site is underlit, replacing the old fixtures with a “similar” LED output may preserve the problem rather than solve it. Dirt depreciation, aging optics and maintenance history should be reviewed as part of the baseline rather than treated as secondary details.

LED and HID Optics Are Different

The same lumen output does not guarantee the same lighting result.

LED luminaires and HID luminaires may distribute light differently. A LED retrofit can change:

• Beam shape.
• Edge coverage.
• Vertical visibility.
• Near-field brightness.
• Target-zone overlap.
• Glare direction.
• Spill light.
• Uniformity.

Final selection should therefore compare photometric distribution, not only input wattage.

Existing Acceptance Criteria May Have Changed

A site originally designed many years ago may no longer meet current owner requirements, safety expectations, camera-visibility requirements or tender criteria.

A retrofit project should confirm the post-retrofit target before selecting LED wattage.

Three High Mast LED Retrofit Paths

There are three common retrofit paths. The correct path depends on the existing system condition, project budget, risk tolerance and required performance. IES commentary on retrofit risk also highlights that installing LED technology into equipment originally designed for another light source can create compatibility risk, so retrofit and replacement should be evaluated carefully.

Retrofit Option	Main Advantage	Main Risk	Best Use
Lamp-only replacement	Lowest intervention	Thermal, electrical and optical compatibility risk	Limited compatible cases
Retrofit kit	Reuses part of existing housing	Listing, thermal and photometric review needed	Sound existing housings with verified compatibility
Complete LED luminaire replacement	Best optical and control flexibility	Higher initial work	Most high-mast engineering retrofit projects

Lamp-Only Replacement

Lamp-only replacement means replacing the old light source with an LED lamp while keeping much of the existing fixture body.

This approach may appear attractive because it reduces installation work.

However, it can present significant thermal, electrical and optical compatibility risks, especially when the existing housing was not designed for the proposed LED source.

Main concerns include:

• Thermal management.
• Optical mismatch.
• Existing reflector condition.
• Driver or ballast compatibility.
• Fixture safety.
• Photometric uncertainty.
• Certification or listing implications.
• Limited aiming control.

For engineering high mast projects, lamp-only replacement should be used only when compatibility is clearly verified.

Retrofit Kit

A retrofit kit replaces some internal components while reusing part of the existing fixture housing.

This approach may reduce cost compared with complete replacement, but it still requires review.

Check:

• Thermal path.
• Mechanical fit.
• Driver mounting.
• Surge protection.
• Wiring condition.
• Lens and reflector condition.
• Photometric file for the final assembly.
• Applicable safety and listing requirements.
• Maintenance access.

A retrofit kit should not be selected only because it fits the old housing physically. It must also meet photometric, electrical and thermal requirements.

Complete LED Luminaire Replacement

Complete LED luminaire replacement is often the most practical approach for high mast engineering retrofit projects.

It allows the project team to select:

• New optics.
• New LED luminaire output.
• New drivers.
• New surge protection.
• New brackets.
• New aiming method.
• Dimming or smart controls.
• IES/LDT files for simulation.
• Better maintenance planning.

For ports, logistics yards, highways, industrial areas and municipal infrastructure, complete luminaire replacement generally provides the greatest flexibility for photometry, thermal management, drivers, controls and project acceptance.

Step 1: Audit the Existing High Mast System

A retrofit project should begin with a complete audit of the existing installation.

Do not start by asking only for old lamp wattage.

Existing System Audit Table

Field	Existing Condition	Evidence Required
Mast ID and location		Site drawing / photo
Mounting height		Survey / drawing
Fixture quantity per mast		Site count
Lamp type and wattage		Nameplate / maintenance record
Ballast or system input watts		Nameplate / measurement
Existing optic or reflector		Datasheet / photo
Aiming direction		Field survey
Current illuminance		Measurement grid
Failure condition		Maintenance record
Control method		Electrical cabinet / control panel record
Cable condition		Site inspection
Corrosion condition		Pole and headframe inspection
Lowering system condition		Maintenance record / test operation

The audit should identify whether the retrofit is only a lighting upgrade or also a structural, electrical or maintenance-risk project.

Step 2: Measure Current Lighting Performance

Existing lighting measurement is valuable because it shows what the site actually receives, not what the old design originally promised.

Measure or document:

• Average horizontal illuminance.
• Minimum illuminance.
• Uniformity.
• Dark zones.
• Hot spots.
• Glare complaints.
• CCTV visibility.
• Critical task areas.
• Boundary spill light.
• Failed or underperforming fixtures.

Measurements should be taken using a defined grid and under known operating conditions. Record the meter type and calibration status where required, ambient-light condition, weather, time, operating fixture count, measurement plane, grid boundary, abnormal points and any failed luminaires. Without these conditions, two measurement records from different dates may not be comparable.

If a measurement grid is not possible, collect photographs, site drawings, mast locations, fixture quantities, mounting height, existing aiming direction and user complaints.

A retrofit proposal should make clear whether it aims to:

• Maintain existing lighting level while saving energy.
• Improve lighting level.
• Improve uniformity.
• Reduce glare.
• Improve CCTV visibility.
• Add dimming or controls.
• Reduce maintenance.
• Comply with a new specification.

These are different objectives. They may require different LED solutions.

Step 3: Set the Post-Retrofit Acceptance Criteria

Before selecting LED fixtures, define what the retrofit must achieve.

Post-retrofit criteria may include:

• Maintained average illuminance.
• Minimum illuminance.
• Uniformity convention.
• Calculation plane.
• Vertical illuminance.
• CCTV visibility.
• Glare limit.
• Spill-light limit.
• CCT and CRI.
• Dimming schedule.
• Control function.
• Energy-saving target.
• Maintenance interval.
• Tender or consultant requirements.

The acceptance criteria should be written before quotation.

Otherwise, the supplier may optimize the proposal for lower wattage, lower fixture cost or easy installation without meeting the actual project objective.

For lighting-level specification, review the High Mast Lighting Level Specification Guide.

Step 4: Check Pole, Headframe and Lowering System Compatibility

High mast LED retrofit is not only a luminaire selection task. The existing pole and headframe must be checked.

Pole, headframe, foundation and lowering-system suitability should be confirmed by qualified parties under the applicable structural and safety requirements. Electrical modifications, ballast bypass, grounding and circuit protection should be completed by qualified personnel according to local codes and lockout/tagout procedures.

LED luminaires may be lighter, heavier, smaller or larger than the existing fixtures. Their effective projected area may also be different.

Lower LED wattage does not automatically mean lower weight, lower wind load or lower structural risk.

Mechanical Compatibility Table

Item	Existing System	Proposed LED System	Must Verify
Fixture weight			Headframe and lowering-system capacity
Effective projected area			Wind-load impact
Fixture dimensions			Clearance and aiming
Bracket interface			Hole pattern and mounting hardware
Total ring load			Structural compatibility
Cable and connector			Fit, rating and condition
Corrosion condition			Pole and headframe safety
Aiming range			Required target-zone direction
Maintenance access			Safe installation and service
Lowering system operation			Load balance and safe lowering

Structural impact should be reviewed using actual fixture weight, dimensions, effective projected area and mounting arrangement.

Do not judge headframe compatibility by LED wattage alone.

Step 5: Check Wiring, Drivers, SPD and Controls

LED drivers behave differently from HID ballasts.

An old electrical system that handled HID loads may still need review for LED operation.

Electrical Compatibility Table

Item	Retrofit Review Point
Existing voltage and frequency	Confirm compatibility with LED drivers
HID ballast	Remove, bypass or replace according to design
Actual system input power	Establish the real energy baseline
Power factor and THD	Check power-quality impact
Inrush current	Confirm breaker, contactor and circuit behavior
Surge protection	Confirm SPD level and grounding
Branch circuit	Check cable, terminal and breaker capacity
Control circuit	Confirm switching, dimming or smart-control compatibility
Driver location	Confirm thermal and service conditions
Cable condition	Check aging, insulation and connector safety
Earthing / grounding	Confirm surge and safety performance
Dimming protocol	Confirm 0–10V, DALI, timer, smart control or other method
Ambient temperature	Confirm driver and luminaire derating
Distribution cabinet	Check breaker, contactor and protection coordination

In some retrofit projects, LED input power is lower than HID. That does not eliminate electrical review.

For example, LED drivers can have different inrush-current behavior. Surge protection may also need improvement, especially for exposed high mast installations.

Step 6: Compare LED Photometry and Aiming

LED retrofit success depends heavily on optics.

The replacement luminaire should be selected with an actual IES/LDT photometric file.

Compare:

• Total luminaire lumens.
• Luminaire efficacy.
• Beam distribution.
• Candela distribution.
• Intensity at required aiming angles.
• Asymmetric or symmetric optics.
• Tilt angle.
• Rotation angle.
• Spill-light control.
• Glare direction.
• Edge coverage.
• Vertical visibility.

Do not assume that a lower-wattage LED fixture with a high lumen package will automatically match the old HID system.

In many cases, the LED system should not copy the old aiming exactly. The new optical distribution may require a new aiming schedule.

For wattage selection principles, review the High Mast Light Wattage Guide.

Step 7: Verify the Retrofit in DIALux

A LED retrofit should be simulated in DIALux, Relux or equivalent software before final approval.

The simulation should compare the proposed LED layout against the project target.

It may also compare the existing system if reliable photometric data is available.

DIALux Retrofit Review Items

Report Item	What to Check
Existing mast locations	Are real locations used?
Mounting height	Does it match the existing pole?
Luminaire quantity per mast	Does it match the proposed retrofit?
IES/LDT file	Is the proposed LED fixture file used?
Rated lumens	Does the file match the datasheet?
Input power	Does it match the proposed configuration?
Optic	Does it match the quoted product?
Aiming schedule	Is tilt and rotation realistic for installation?
Maintenance factor	Is maintained performance reviewed?
Calculation grid	Does it match the required area?
Average illuminance	Does it meet the target?
Minimum illuminance	Are dark zones controlled?
Uniformity	Is the correct convention used?
Glare	Are operators, drivers or neighbors affected?
Spill light	Are boundaries controlled?

An IES file should also be cross-checked against the datasheet and applicable test report.

A photometric file should not be accepted only because it imports successfully into DIALux.

Step 8: Run a Trial Mast or Mock-Up

For larger retrofit projects, a trial mast or mock-up can reduce risk.

A trial helps verify:

• Mechanical fit.
• Bracket compatibility.
• Aiming adjustment.
• Driver behavior.
• Control response.
• Light distribution.
• Glare perception.
• Maintenance process.
• Commissioning procedure.

A trial mast is especially useful when:

• The site has high operational risk.
• Existing drawings are incomplete.
• Old pole condition is uncertain.
• The retrofit changes optics significantly.
• The project involves ports, airports, mining areas or highways.
• The owner requires visual confirmation before full deployment.

The trial should not replace calculation. It should confirm that calculation and site reality are aligned.

Step 9: Commission the Installed Retrofit

A retrofit is not complete when the new LED luminaires are installed. Commissioning should confirm that the installed system matches the approved retrofit proposal.

Check:

• Installed luminaire model.
• Installed wattage or power setting.
• CCT and CRI.
• Optic type.
• Fixture quantity per mast.
• Final tilt and rotation.
• Bracket and fastener condition.
• Driver settings.
• Surge protection.
• Control and dimming operation.
• Actual circuit power.
• Post-installation illuminance.
• Glare or spill-light issues.
• As-built aiming schedule.
• Updated maintenance record.

Commissioning is especially important when the project uses dimming, power-selectable luminaires, smart controls or revised aiming.

Step 10: Verify Energy and Maintenance Savings

After commissioning, compare post-retrofit energy use with the approved baseline.

The comparison should be normalized for:

• Operating hours.
• Dimming schedule.
• Actual circuit power.
• Seasonal operating changes.
• Material changes in site operation.
• Failed or disabled fixtures.
• Maintenance events.

If the project uses dimming, do not calculate energy only from rated power multiplied by total hours. Use the actual dimming power curve, metered data or confirmed power data for each operating profile.

Maintenance savings should also be checked against real service records, not only expected LED lifetime.

Energy Savings and Lifecycle Cost Review

Energy saving is a major reason for high mast LED retrofit.

However, energy saving should be calculated with real system assumptions.

Do not calculate savings only from lamp wattage.

A basic screening calculation can use:

Baseline annual energy =
existing measured system kW × annual operating hours

Post-retrofit annual energy =
LED system kW × equivalent full-load operating hours

Annual energy savings =
baseline annual kWh − post-retrofit annual kWh

Annual cost savings =
energy savings × electricity tariff

If dimming is used, equivalent full-load operating hours should be based on the confirmed dimming schedule and power data, not only rated power multiplied by clock hours.

Use:

• Actual existing system input watts.
• Proposed LED system input watts.
• Quantity of luminaires.
• Annual operating hours.
• Dimming schedule.
• Electricity cost.
• Maintenance cost.
• Lamp replacement cost.
• Lift truck or lowering-system cost.
• Failure rate.
• Cleaning interval.
• Control strategy.

Energy Saving Calculation Table

Item	Existing HID System	Proposed LED System
Quantity
Lamp wattage
Ballast / driver input watts
Total system kW
Annual operating hours
Dimming schedule
Annual kWh
Electricity cost
Maintenance cost
Annual cost
Estimated annual savings

Simple payback can be useful for early screening, but lifecycle cost is better for formal project review. DOE financial-analysis guidance similarly emphasizes that first-level payback can miss important economic factors and that full life-cycle cost/benefit review is more suitable for informed decisions.

Lifecycle cost may include:

• Fixture cost.
• Installation cost.
• Electrical modification.
• Control upgrade.
• Maintenance reduction.
• Energy saving.
• Spare parts.
• Downtime.
• Warranty and service conditions.

A retrofit proposal should not promise savings without showing the calculation basis.

Can a 1000W Metal Halide High Mast Light Be Replaced by LED?

Yes, in many projects a 1000W metal halide high mast light can be replaced by LED.

However, the replacement LED wattage is not fixed.

The correct LED option depends on:

• Existing system input power.
• Current lighting level.
• Existing luminaire condition.
• Pole height.
• Fixture quantity per mast.
• Existing beam distribution.
• Required maintained lighting level.
• LED luminaire efficacy.
• LED photometry.
• Aiming plan.
• Glare control.
• Electrical compatibility.
• Mechanical compatibility.

A 1000W metal halide replacement may be shortlisted using LED products with lower input power, but final selection should be verified with IES/LDT files and DIALux.

Do not approve a retrofit only because a product page claims a fixed LED equivalent.

Can a 1500W or 2000W HID High Mast Light Be Replaced by LED?

Yes, but higher-output HID retrofit projects require more careful engineering review.

A 1500W or 2000W HID system may involve:

• Large existing fixtures.
• Heavy headframes.
• High mounting heights.
• Wide-area lighting.
• Higher electrical load.
• Specific optical requirements.
• Large target zones.
• Higher glare risk.
• More complex maintenance access.

LED replacement may reduce energy and improve optical control, but it must be checked for:

• Required lumen package.
• Candela distribution.
• Fixture quantity.
• Headframe load.
• Effective projected area.
• Bracket compatibility.
• Driver behavior.
• Surge protection.
• DIALux results.
• Lighting acceptance criteria.

For high-output HID systems, one-to-one fixture replacement may not be the best solution. The project may need a revised luminaire quantity, new optics or a new aiming plan.

HID to LED Retrofit Screening Table

The following table is for early screening only. It is not a final replacement chart.

Existing HID System	Preliminary LED Screening	Why No Fixed Equivalent	Required Verification
1000W metal halide / HPS	No fixed LED wattage	Existing system power, lamp age, optics and pole height vary	Current measurement, IES/LDT, DIALux, maintained lux
1500W metal halide / HID	No fixed LED wattage	LED size, weight, EPA, beam distribution and driver behavior differ	Structure, aiming, electrical load, glare
2000W HID	Project-specific	One-to-one replacement may fail uniformity or glare control	Full photometric, structural and electrical assessment
Existing HPS system	Project-specific	LED changes color, CRI, optical direction and visibility	CCT, CRI, glare, target zones, controls

This table avoids a misleading fixed equivalent.

A project may still create an internal shortlist, but that shortlist must be verified before procurement.

Retrofit Decision Framework: Fixture Replacement vs System Redesign

Not every retrofit should be a direct fixture replacement.

Use the following framework.

Situation	Fixture Replacement May Be Enough	System Redesign May Be Needed
Existing lighting level	Already acceptable	Current site is underlit or uneven
Pole locations	Suitable	Poor mast locations or major shadows
Headframe condition	Good and compatible	Corroded, overloaded or incompatible
Electrical system	Compatible with LED drivers	Old wiring, poor protection or control limitations
Optics	New LED optics fit the same target zones	Aiming and distribution must change
Glare complaints	No major issue	Retrofit must reduce glare or spill light
Controls	Simple switching acceptable	Dimming, smart control or monitoring required
Project risk	Low	High-risk site such as port, highway, airport or mining yard

A direct replacement may save time, but a system redesign may produce better lighting performance and long-term value.

RFQ Checklist for High Mast LED Retrofit

A complete retrofit RFQ should include the following information. For public or tender-driven projects, product selection should also align with the relevant owner specification, roadway/exterior-lighting procurement requirements and luminaire performance documentation.

RFQ Item	Why It Matters
Site location and application	Defines operating conditions and lighting objective
Existing mast layout	Required for DIALux and retrofit review
Pole height	Determines mounting height and aiming
Fixture quantity per mast	Defines headframe and output comparison
Existing lamp type and wattage	Starting point for retrofit review
Existing ballast or system input power	Required for real energy-saving calculation
Existing fixture photos	Helps evaluate mounting, optic and condition
Existing aiming direction	Helps compare current and proposed layout
Current lighting measurement	Defines actual baseline
Required post-retrofit lighting level	Defines acceptance criteria
Uniformity requirement	Controls dark zones
Existing electrical data	Confirms voltage, circuits, controls and protection
Headframe and lowering-system data	Confirms mechanical compatibility
Control requirement	Defines timer, dimming or smart monitoring options
DIALux report requirement	Supports engineering approval
BOQ format	Supports procurement and tender comparison

The more complete the RFQ, the more accurate the retrofit proposal will be.

Common Retrofit Mistakes

Mistake	Why It Creates Risk	Better Review Method
Using a fixed HID-to-LED wattage chart	Ignores optics, pole height and existing performance	Use charts only for early screening
Ignoring ballast losses	Understates existing energy use	Measure or estimate system input power
Ignoring existing degradation	May preserve underlit conditions	Measure current lighting level
Copying old aiming	LED optics may distribute light differently	Create a new aiming schedule
Ignoring headframe load	New LED fixtures may differ in weight and EPA	Check mechanical compatibility
Ignoring LED driver behavior	Inrush current and control behavior may differ	Review electrical system
Accepting IES files without cross-checking	Files may not match the quoted configuration	Compare IES/LDT, datasheet and test report
Skipping DIALux	Retrofit may fail uniformity or glare	Simulate before procurement
Focusing only on watts saved	Lighting quality may decline	Compare performance, maintenance and lifecycle cost
No trial mast on high-risk sites	Site conditions may differ from drawings	Test before full deployment

Engineering References

The following references support the engineering logic used in retrofit review. They should not be read as fixed high mast wattage-equivalent charts.

• DOE Roadway Lighting Research — useful background for LED outdoor lighting performance, optical controllability and controls-based energy reduction.
• DOE Trial Demonstration of Area Lighting Retrofit — useful context for field trial and retrofit demonstration thinking.
• DOE Model Specification for LED Roadway Luminaires — useful for specification-based LED luminaire procurement.
• DOE Purchasing Energy-Efficient Exterior Lighting — useful for energy-efficient exterior lighting purchasing context.
• DOE Financial Analysis — useful for lifecycle-cost and payback review.
• IES: Managing Retrofit Risk — useful context for retrofit versus replacement risk.
• DOE Luminaire Dirt Depreciation Field Data — useful context for dirt depreciation and baseline maintenance assumptions.

Request a High Mast LED Retrofit Review

High mast LED retrofit should be reviewed before procurement, especially when the project involves existing metal halide, HPS or HID high mast systems.

Send us your existing mast layout, fixture quantity, pole height, lamp type, fixture photos, electrical information, current lighting measurements, target performance and retrofit objective. Sunlurio can help review LED luminaire options, IES/LDT files, DIALux results, mechanical compatibility, electrical requirements and BOQ preparation.

Request a High Mast LED Retrofit Review

Related High Mast Lighting Guides

The following guides explain related decisions in high mast lighting and retrofit projects:

• High Mast Light Wattage Guide
• High Mast Lighting Level Specification Guide
• High Mast Lighting Design Guide
• High Mast Pole Height Guide
• High Mast Pole Spacing Guide
• High Mast Lighting Layout Patterns
• How Many High Mast Lights Do You Need?
• High Mast Lighting Coverage Explained
• High Mast Lighting Systems
• Engineering Support for Lighting Projects
• DIALux Simulation Outputs
• IES/LDT Photometric Files
• Tender Documents and BOQ Support

Frequently Asked Questions

What LED wattage replaces a 1000W metal halide high mast light?

There is no fixed LED wattage. The correct replacement depends on existing system input power, current lighting level, pole height, fixture quantity, optics, LED photometry, maintained lighting target and DIALux verification.

Can I replace HPS high mast lights with LED?

Yes, HPS high mast systems can often be replaced with LED. The retrofit should review CCT, CRI, visibility, glare, optics, controls, electrical compatibility and maintained lighting performance.

Is a HID-to-LED wattage chart useful?

It can be useful for early screening, but it should not be used for final approval. High mast retrofit must be verified by photometric calculation, structure and electrical compatibility.

Do I need DIALux for high mast LED retrofit?

For engineering, municipal, port, industrial, highway or consultant-reviewed projects, DIALux, Relux or equivalent calculation is strongly recommended. It helps verify maintained illuminance, uniformity, glare and target-zone coverage.

Can I reuse the existing high mast pole and headframe?

Possibly. The existing pole, headframe, brackets and lowering system must be checked against the proposed LED fixture weight, dimensions, effective projected area, total ring load and mounting arrangement.

Do I need to remove the old HID ballast?

Complete LED luminaire replacement normally removes the obsolete HID ballast. Ballast-compatible replacement lamps are a separate product category and must be explicitly listed as compatible with the installed ballast. The exact method depends on the selected LED product, site wiring and local electrical requirements.

Will LED retrofit always reduce energy cost?

LED retrofit often reduces energy use, but savings should be calculated using actual system input power, operating hours, dimming schedule, electricity price and maintenance cost. Do not calculate savings from lamp wattage alone.

Can LED retrofit create glare?

Yes. LED retrofit can create glare if optics, aiming, mounting height and observer positions are not reviewed. Lower wattage does not automatically guarantee lower glare.

What information should I provide for a retrofit proposal?

Provide mast layout, pole height, fixture quantity per mast, existing lamp type, ballast or system input power, fixture photos, current lighting measurements, electrical data, target lighting level, control requirements and required report format.

When should a retrofit become a full system redesign?

A full system redesign should be considered when existing lighting is poor, pole locations are unsuitable, headframes are corroded, electrical systems are outdated, glare complaints exist, or the project requires new lighting levels, controls or approval standards.