Helios-75K Floodlight™

Master-Lee would like to introduce the brightest “drop-style” LED light on the market, the Helios-75K Floodlight™.  Designed to be as powerful as a large floodlight but compact and rugged enough to play the role of an area drop light, the Helios-75K Floodlight™ shines brightly in any environment.  In-air or underwater, this dimmable LED light offers more than enough light for illuminating large areas.

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SKU: D3183 Category: Tags:


Providing up to 78,000 lumens of dispersed, white light using the latest in LED technology, the Helios 75K™ is best suited for lighting large underwater areas, such as reactor cores and spent fuel pools, or in-air areas such as refueling cavities. The Helios-75K Floodlight™ has been engineered to be compact, lightweight, rugged, yet versatile to be quickly deployed to nearly any working environment underwater or in open air to compete with it’s big brother, the Helios-100K Floodlight™, for center stage.  Designed to operate at depths to 150-ft and within close proximity to irradiated fuel assemblies, the Helios-75K Floodlight™ is the ideal solution to illuminate reactor cores for video inspections or fuel movement.  Such a high light output gives our customers the flexibility to do more with less, as the Helios-75K Floodlight™ can provide the illumination of two or more traditional (tungsten/quartz halogen) lights.  This not only reduces the amount of required electrical outlets, as two Helios-75K Floodlight™ lights operate on one 15-Amp circuit, but also the amount of time spent positioning lights within the core is reduced.  Additionally, incorporating LED lighting technology provides thousands of maintenance-free operating hours, reducing your re-lamp, installation, and removal times.


With the capacity to produce up to 78,000 lumens of crisp, bright light there comes a point where changing conditions necessitate adaptation and that level of intense lighting can become overwhelming and counterproductive. Fully dimmable from 100% output to 10% power gives the end user total control allowing the light to perform exactly as needed. If it’s not the user adjusting light output based on conditions, it’s the conditions adjusting light output. The Helios-75K Floodlight™ incorporates a unique safety feature, Auto-Dimming, to protect itself from thermal overload. When the Helios-75K Floodlight™ is removed from water, its primary cooling medium, its operating temperature begins to rise. As this occurs, it senses the temperature increase and begins to lower its light output to maintain a safe operating level. In the warmest of open-air working environments, the Helios-75K Floodlight™ will effectively and safely cool itself through natural convection, operating down to 50% power levels if required. When conditions require fine control over light output, the end user can adjust this via a dimmer knob located on the Power Console.


Constructed of aluminum and finished with hard anodize, the Helios-75K Floodlight™  weighs under 15 pounds (5 pounds in water) for easy, manual installation/removal.  With the detachable cord secured to the light head with strain relief cord grips, the light is designed to hang from its cable in nearly any industrial environment.  The Helios-75K Floodlight™ System includes (1) Light Assembly w/ strain relief cord grip, (1) Power Console, (1) 75′ removable power cord, and (1) lens replacement kit.  Operating on standard 110-VAC or 220-VAC (DC input voltage is an available option) and drawing under 7-Amps adds to the portability and permits multiple lights to be configured on one electrical circuit.



Light output  Up to 78,000 lumens
 Light color  5000K (white light)
 Beam pattern  Flood
 Radiation tolerance  No limit (Lens needs monitoring w/ very high doses)
 LED Life  50,000 hours (> 70% lumen output)
 Dimming  100-10% manual; 100-50% auto
 Materials  Anodized aluminum; polycarbonate (lens)
 Operating temp (°F) 165 (maximum, in-air); ~135 (in water)
 Power Factor  92 – 98%
 LED Efficacy (@85C)  152 lumens/watt
 Warranty  1-Year; Limited; Parts replacement

 Operating voltage  100-240 VAC input
 Operating current   Up to 7.0 Amps
 Depth rating  Up to 100-feet
 Assembled weight  15 lb (Light head)
 Light Panel Size  10″ Diameter x 3.5″ High
 Light head positions  Vertical (0-deg) to 45 deg
 Cord  100-ft, Integral Rubber
 Protection  Thermal Overload; Short Circuit,
Over Voltage; Fuse Protection
 LED Flux (@85C)  70,900 lumens
 FME Equipped  Yes

Part Image Part Description EPI Part No.
  Helios-75K Floodlight™ System, includes:
– (1) Power Console
– (1) Helios 75K™ Light Head
– (1) 75-ft detachable power cord w/ strain relief
– (1) Lens Replacement Kit
Replacement Parts (Sold Individually)

Helios-75K Floodlight™ Light Head Assembly

w/ 100′ integral cord


Helios-75K Floodlight™ Power Console

w/ AC power cord

Helios-75K Floodlight™ Lens Replacement Kit, includes:
– (1) Polycarbonate Lens (P/N: C3187)
– (1) O-Ring
– (1) 1-oz pack of Molykote lubricant