Register Here | Login | My Account | Shopping Cart | Customer Service | Search| Items in Cart (0) | Quotes (0)
Call 1-800-369-6671
(Military/Intl Sales - 214-616-6180)

Vast Inventory for Fast Shipping. Custom Builds Available, Rentals and Sales.
Most items in stock for fast shipping!! UPS Ship Map Credit cards & Paypal Accepted
Home - Articles You're NOT logged in, Please log in   

Company Information

Product #:

ATEX and IEC Ex Flame-proof Explosion Proof Lighting & Equipment
Explosion Proof Lights
Explosion Proof Motors - Motors for Hazardous Locations
Industrial and Vaporproof Emergency Failsafe Lighting
Industrial Cord Reels and Tool Taps
Industrial Work Area Heaters
Machine Vision Lights
QC Series Industrial Portable Lighting - Quick Change Mount
Rig Lights
Stadium lights
String Lights and Temporary Light Stringers
Tank Cleaning Lights
Three Phase Motor Soft Starters
Vapor Proof LED Lights
Variable Frequency Drives (VFDs)
Vehicle Mounting Plates
Workboat Light Fixtures & Lighting Equipment
Yacht Engine Room Lights
Color Changing LED RGB Lighting
Explosion Proof Cord Reels
GOLIGHT Spotlights
Larson FUTURE - Lease Lighting
Remote Area Lighting and Scene Lights
Utility Bucket Mount, Receiver Hitch & Trailer Mount Lighting
Aevum Control Lighting and Equipment - IIoT
Butane and Solvent Extraction Room Lighting and Equipment
DC to DC Transformers and Power Supplies
Explosion Proof Fans & Blowers
Explosion Proof Paint Spray Booth Approved Lights
Explosion Proof String Lights
Explosion Proof Switchgear & Controls
Fleet Service Lights and Lighting Equipment
Industrial Equipment Trailers
Industrial Handlamps & Droplights
ISO 14644/FS-209E Clean Room Lighting
LED Blasting Lights
Night Time Fishing Lights
Portable AC Power Supply Units
Portable Power Distribution Panels
Power Distribution Panels with KVA Transformers
Self-Contained Lighting
Service Pit Lighting
Solar Generators & Solar Powered Lighting
Agricultural Farm Equipment Lighting & Beacons
Explosion Proof Cameras & Surveillance Systems
Explosion Proof Emergency Lights
Explosion Proof Heaters
Garage & Gas Station Canopy Lights
LED Grow Lights
LED Lights
NDT Ultraviolet Lights
Portable Hazardous Location Lighting
Radio Communication Towers and Equipment
Salt Water Processing Equipment
Shelter & Tent Lighting
Thermal Monitoring Cameras and Systems
48V LED Equipment Lights
ATEX Rated Explosion Proof Lights
Automotive Lighting
Class Rated Signals, Alarms, and Systems
Hazardous Location Area Lights and Portable Lighting
HID Equipment Lights
Hot Work Permit Lighting and Equipment
Hunting Lights
Industrial lasers
Industrial Transformers
Light Towers
Outdoor Lighting
Remote Security and Surveillance Systems
Temporary Construction Lights
Vehicle Mounted Spotlights
Equipment & Heavy Machinery LED Light Package Fitouts
Phase Converters - Single to Three Phase
Marine Shore Power Cords and Equipment
24 Volt Military Lights
Disaster Relief / First Responders / Search & Rescue Lighting
Plastic Handcuff Key
110/120 Volt Flood Lights
Post Mount Spotlights
Magnetic Work Lights
Crank-up Light Masts
Intrinsically Safe Lights
Military Flashlights
LED Waterproof Lanterns
Work Area Lights
12 Volt Flood Lights
Boat Spotlights
New Boat Lights
HID Boat Lights
Boat Dock Lights
Remote Control Lights
Control Lights
Tow Lights
Magnetic Control Lights
NEW Lights and New Products
Evaporative Coolers
Police Equipment
AC/DC Transformers
Power Supplies
Military Spotlights 24V
Infrared Filters, Covert Covers, and Blackout IR Lenses
Military Equipment
Ultralife Batteries
Remote Control Pan Tilt Base
Larson Electronics Spotlights
Larson Electronics Parts
Replacement Lamps
Cords - Brackets
Portable Wheeled Generators
Non-Hazardous Location Extension Cords / Plugs / Outlets
HID Work Lights
HID Dive Lights
HID Off Road Lights
Acro Lights HID Lights
Halogen Lights
Acro Light Flashlight
Xenon HID Flashlights
Powerlight Flashlight
HID Flashlights
Xenon Flashlights
LED Status Lights
Forklift Lights
Tractor Lights
HID Post Mount Lights
Roof Mount Lights
Post Mount Light parts
Flashlight Holder
Magnet Spotlight Base
Tripods-Magnetic Base
Recharging Spotlights
Fire Rescue Lights
LED Street Lights
Utility Lights
Hazard Lights
Strobe Lights - Battery Operated
Strobes & Beacons
Strobe Light Bars
Headlights - Headlamps - Hard Hat Lights
Suction Mount Lights
Magnetic Spotlights
12/24 Volt Spotlights
Gifts For Men
New 12 / 24 Volt Lights
Explosion Proof Accessories and Replacement Parts
Explosion Proof Lighting
Explosion Proof Hand Lamps (Drop Lights)
Explosion Proof Lights - Stand/Dolly
Explosion Proof Tank Lights
Explosion Proof Phones and Intercoms
Explosion Proof Extension Cords
Black Friday & Cyber Monday Specials
Crane Lights
Explosion Proof Light Rentals
General Light Rentals
Light Tower and Light Plant Rentals
Power Distribution Rentals
Power Plant Lighting
Refinery lights
Environmental Services Lights
Aerospace Lights
Chemical Plant Lights
Food Grade Safe Lights
Film and Entertainment Lights
Handheld Meters and Devices
Waste Water Treatment Lights
Mining Lights
Ship Yard Lights
Work Site Lighting

12/20/11 Temporary Power Distribution Within Industrial Construction Projects

Article- December 2011 By Larson

Portable Temporary Power Substation

Larson Electronics Portable Temporary Power Substation

Under normal conditions, providing power for electrical equipment is as simple as plugging into a wall outlet. For many industrial jobsites however, conditions are anything but normal. Particularly in new construction involving large scale projects, providing power becomes a large scale project all on its own. With no established power supplies, no existing distribution systems, and the need to provide power for a large variety of equipment requiring everything from high voltages to common 110-120 VAC current, providing power becomes a major issue. In many cases, contractors must develop a complete power supply and distribution system of their own that can not only meet the needs of equipment, but serve only in a temporary capacity and be removed once the project is completed as well. 



Because of the large scale and extended duration of many industrial construction projects, the need for electrical power requires power systems that while temporary, have all the functionality and reliability of permanent connections to the local grid. Meeting these requirements are a challenge due to the voltages involved and the need to maintain safety as well as make electrical power readily available throughout the entire structures involved. In most cases, electrical contractors are consulted who develop an electrical plan based on the size and load requirements of a particular site. These contractors often consult with local utilities who then provide access to a very high voltage primary power source, which the contractor must then step down to useable levels and distribute throughout the project area.



Problems encountered with providing temporary power to industrial job sites include adhering to OSHA regulations, providing enough load handling capability, and reducing the chances of voltage drops, overloads, and overheating that could arise due to excessive cord lengths and insufficient connection points resulting in overloaded lines. Contractors meet these issues through the use of large temporary substations to manage high primary voltages, carefully installed temporary conduit or wiring systems for distribution of this reduced voltage, and multiple step down distribution transformers which provide useable end voltages. The result is nothing less than an entire power grid system of a temporary nature with all the functionality of normal permanent connections.



The electrical power utilized by contractors often starts out as a primary high voltage connection to the local grid. These voltages vary according to the utilities involved and can exceed 11,000 volts. The first step is to reduce this to manageable voltages through the use of temporary power substations which reduce this current to 480VAC. Once this is achieved, the 480VAC power can be fed into distribution panels for routing through the structure. To provide power to every location within the structure, conduit or wiring is run to every level and or most convenient point and terminated at each location with an access made up of receptacles, panels, or other similar connecting points. With 480VAC current now available at the required locations within the site, it is then necessary to further reduce this current to useable levels and provide easy access for connection to equipment.



Power for equipment is normally required to be 110, 120, 208 and 220-240 for power lighting, fans, drills, motors, welders and other construction equipment. Additionally, cords should not exceed 100 feet in length in order to avoid voltage drops and cord overheating, so access to these voltages needs to be convenient. To step down the supplied 480VAC power, smaller temporary transformer/distribution centers are installed at each 480VAC access point and connected. These portable step down transformers come in a wide variety of configurations, but generally contain a 480VAC primary input side, which is then stepped down via a small transformer to 110, 120, 208 and 220-240 VAC. These transformers feed this power through breaker and or fuse protected circuits which in turn fed integral secondary output receptacles which may or may not be GFI/GFCI protected depending upon the distribution center’s configuration and worksite requirements.


These distribution centers must manage a wide range of loads and be suited to the particular conditions they will be operated under. For instance, some welding equipment requires very high voltages to operate, and thus 120-220 will be insufficient. As a result, the transformer/distribution center will require additional feed through capability to provide direct 480VAC current. In other applications, wet conditions or hazardous flammable materials may be present. In these instances, distribution centers will require at least an IP67 waterproof rating in the case of exposure to wetness, or hazardous location certification in the case of flammable environments.


Additionally, it is necessary to assume the highest possible loading that may occur and install power step down and distribution systems that will allow a safe margin for error. A system with load handling capability which exceeds load requirements presents little problems, but one with insufficient capability can be easily inadequate if expected loads are accidently exceeded by a small margin. Although grounding and breaker/fuse protection may provide the necessary precaution against faults and overloading, frequent system shutdowns due to overloading can have a serious impact on productivity and still potentially lead to workplace accidents. Also, the transformer needs to be situated so that all equipment operated will be within 100 feet of the system to avoid excessive cord lengths and thus protected against voltage drops.


Another consideration for installation of portable step down transformers and distribution centers is their size and weight. The transformers and materials used can lead to systems that although portable, are anything but easily relocated. For large scale sites, transformer systems are often quite heavy, and as a result are best configured as self contained systems which can be easily managed with small forklifts or lifting equipment. With the transformer, circuits, breakers and receptacles all contained within a single package encased within a solid frame or similar housing, it is a simple matter for operators to relocate the system to a desirable position using powered transport.



Providing power for large scale industrial construction projects is no longer a simple matter of running a few generators and rigging up some lights and outlets. OSHA regulations, site size, and the load requirements of today’s equipment require comprehensive systems that provide safety as well as reliable operation on a temporary basis. These systems in essence represent a miniaturized version of the local power grid and as such, require the same forethought and planning to maintain safety as well as productivity.




Related Categories/Products
Category/Product (click on link below for more information)
Power Distribution Panels with KVA Transformers
110/120 Volt Flood Lights
110/120 Volt Flood Lights
110/120 Volt Flood Lights
Explosion Proof Drop Lights / Trouble Lights / Hand Lamps
Portable Explosion Proof Lights
45KVA Temporary Power Substation - 480V 3P to 208Y/120 3P - (8) L5-30R GFCI Outlets
Vapor Proof 4 Light GFI Cart with Pneumatic Tires - 50 foot cord
25 KVA Temporary Power Distribution Station - 480V to 120/240V 1PH - (6) 120V GFCI Receptacles
Temporary Power Distribution Panel – 37.5 kVA – 480v to 120/240 – 8 X 120V, 2 X 250V outlets
10W Chemical Resistant LED Light - Class 1 Div 2 - Class 2 Div 2 - Non-Metallic -Corrosion Resistant
1000 Watt Metal Halide Light - Hot Restrike - Multi-tap Ballast - Spot or Flood
Power Substation - 15KVA - Converts 480V to 120/240V with 30A feed thru - (10) GFCIs - (2) L6-30R
Power Substation - 15 KVA - Converts 480V to 120VAC and 240V Outlets with GFCI - 30A Feed Thru - 60A
6,000 Watt, Water Cooled Diesel Generator - 30' Telescoping Tower - 4, 1000W Metal Halide
1000 Watt High Pressure Sodium Flood Light - 110,000 Lumens - Slipfitter Mount - 120~277 Volts AC
Home | Contact Us | Return Policy | Privacy Policy | Security Policy | Copyright © 2006-2018. All Rights Reserved.