Helios-75K CoreLite™

Master-Lee would like to introduce the brightest LED core plate light on the market, the Helios-75K CoreLite™.  Designed to compliment it’s bigger brother, the Helios-100K Floodlight™, this compact area light is designed to be quickly and easily positioned in a core plate flow hole for illumination of the lower reactor core in support of refueling activities.  Radiation tolerant, dimmable, operable In-air or underwater, this LED light is perfectly equipped for nearly every situation.

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SKU: D3242 Category: Tags:


Providing up to 78,000 lumens of dispersed, white light using the latest in LED technology, the Helios-75K CoreLite™ is designed to be placed directly on the reactor vessel core plate to illuminate the lower core in support of refueling and inspection service operations. The fully dimmable Helios-75K CoreLite™ has been engineered to be compact, lightweight, rugged, and is specially equipped with a custom pin to secure itself in a flow hole of the reactor vessel core plate.  The ease of positioning the light along with its large area of illumination ensures fewer moves are required by operators during critical path time, ultimately saving time.   Pairing the Helios-75K CoreLite™ with its big brother- the Helios-100K Floodlight™ System –  ensures the entire reactor vessel is brightly illuminated for thousands of hours of maintenance-free operating time.  Such a high light output gives our customers the flexibility to do more with less, as the Helios-75K CoreLite™ 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 CoreLite™ operate on one 15-Amp circuit, but also the amount of time spent positioning lights within the core is reduced.


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 CoreLite™ incorporates a unique safety feature, Auto-Dimming, to protect itself from thermal overload. When the Helios-75K CoreLite™ 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™ CoreLite will effectively and safely cool itself through natural convection, operating down to 30% 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 CoreLite™  weighs 10 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 CoreLite™ System includes (1) Light Assembly w/ strain relief cord grip, (1) Power Console, (1) 75′ removable power cord, and (2) lens replacement kits.  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 (360-deg)
 Radiation tolerance  No limit (Lens needs monitoring w/ very high doses)
 LED Life  50,000 hours (> 70% lumen output)
 Dimming  100-10% manual; 100-30% 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 5.0 Amps
 Depth rating  Up to 100-feet
 Assembled weight  10 lb (Light head)
 Light Panel Size  4″ Diameter x 26″ High
 Light head positions  Vertical (0-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 CoreLite™ System, includes:
– (1) Helios 75K™ Power Console
– (1) Helios 75K™ CoreLite Head w/100′ Integral Cord
– (2) Lens Replacement Kits
D3242 (for 15×15 & 17×17 Fuel)
  Helios-75K CoreLite™ System, includes:
– (1) Helios 75K™ Power Console
– (1) Helios 75K™ CoreLite Head w/100′ Integral Cord
– (2) Lens Replacement Kits
D3243 (for CE 14×14)
Replacement Parts (Sold Individually)
Helios 75K™ CoreLite Head w/100′ Integral Cord D3245
Helios 75K™ Power Console w/ AC power cord D3189
Helios-75K CoreLite™ Lens Replacement Kit, includes:
– (1) Polycarbonate Lens (P/N: C3187)
– (2) O-Ring
– (1) 1-oz pack of Molykote lubricant