Underground Power Distribution Equipment

Nobody knows underground power distribution equipment like we do.

Power Centers/MLCs

Our load centers, built with IE high-efficiency dry-type transformers, form the electrical backbone of any underground mine. Our SmartCenter™ technology integrates key components into a single digital platform and represents the future of underground mining productivity. 

  • Ruggedized mechanical design; low profile options available
  • Standard designs or fully customizable
  • Both step-up and step-down transformers available
  • Dual primary and secondary voltages available
  • Fully manual, or digital / automated (PLC/SmartCenter™) concepts available
  • Draw-out component technology available
  • Up to 25KV class primary voltage
  • Three-phase dry-type transformers up to 10MVA, with dual input voltages and multiple secondary voltages available. 

Custom Dry-Type Transformers

IE designs and manufactures custom dry-type transformers up to 10 MVA and 25 kV.  Our state-of-the-art equipment including a GEORG core cutter machine and specialty test bench allows us to meet the latest DOE energy efficiency codes.  For more information, see our dedicated transformer page.

  • Fully customizable designs
  • Standard designs with custom core steel and copper windings
  • Dual primary and secondary voltages available; taps at +/ 5-10%
  • High efficiency, step-lapped ,miter-cored designs; traditional butt-lapped designs also available
  • Variety of junction boxes (J-boxes) and other disconnect boxes available.
  • Up to 25 kV
  • Meet latest (2015) DOE energy efficiency codes – designs over 99% efficient
  • Standard 150C degree temperature rise, but other standards available

Distribution Boxes / Panels

We offer a variety of ruggedized distribution and breaker panels, including in specialty stainless steel or other enclosures, fully packaged with safety and monitoring controls.

  • Variety of mounting options including skid mounted or wall or ceiling suspended versions
  • Everything from simple breakers and ground fault protection to FVNR starter packages to VFDs with PLC controllers
  • Various options, but all compliant with applicable MSHA regulations in CFR 30

Underground Switchgear and Junction Boxes

IE has a full repertoire of underground switchgear designs, covering traditional metal-clad vertical stack designs for high clearance environments to skidded and ruggedized low-profile switchgear or visual disconnects.  Designs feature multiple Vacuum Circuit Breaker (VCB) and load break switch (LBS) options, including our own IE175VB, a Vacuum Circuit breaker with built-in visual disconnect.

  • Fully customizable designs
  • Ruggedized, portable, low-profile switchgear incorporating VCBs up to 25KV
  • Traditional ANSI-style metalclad options 
  • Fully integrated and tested with feeder protection relays
  • Metering and ground monitoring options available
  • Incorporate isolation and grounding through visual disconnects
  • Variety of junction boxes (J-boxes) and other disconnect boxes available.
  • Up to 25KV
  • Compliant with applicable MSHA regulations in CFR 30

Motor Starters, Controls, and VFDs

We offer a variety of proven designs for line starter packages, and soft-start or VFD controllers for belts, fans, pumps, or other loads.  Our belt controller packages range from small single soft-start packages up to synchronized, quad-600hp load sharing VFD packages.  Integrated cooling, automation, and communications.

  • Ruggedized, mobile designs for line starters, soft-starts, or VFD controllers
  • Deep experience, having packaged over 100,000 hp of VFDs
  • Built in VFD cooling packages with air-to-air heat exchangers for operations in the dirties environments
  • Fully integrated instrumentation, controls, and automations, including custom PLC programming
  • Deep expertise in synchronized VFDs for improving performance through load sharing on large belt systems; regen and other options available
  • Work with MSHA to achieve all required approvals
  • Standard designs up to 600V, with 4160V packages available
  • Low voltage VFD packages featuring drives up to 600hp
  • MSHA compliant / approvals

Mobile Gensets

Ruggedized gensets in low-profile packages up to 600KW or more for tramming underground electrical equipment. Cat or Cummins options including air filtering, built in dry-type transformers for specialty voltages, and ground monitoring on output circuits for MSHA compliance. 

  • Ruggedized, portable, low-profile frame
  • Fully integrate genset, cooling, air filtration, and dry-type transformers
  • Designs with dual or even three output voltages available
  • Output circuits provide ground monitoring for MSHA compliance
  • Wheeled or skidded versions available
  • 480V and specialty voltage (600V, 995V) options available
  • Tier 4 emissions packages available

Underground Substations

Perfect solution for mines that decide to upgrade voltage to reach deeper underground, underground substations provide stepdown power from one MV class to another, most commonly from 5KV to 4160V.  One 5MVA substation can feed six 1000KVA Load Centers.

  • Low-profile design 
  • Stepdown dry-type transformer
  • Generally transform from one MV class to another
  • Transformer protection and/or feeder protection relays 
  • Up to 5 or more distribution circuits
  • Up to 10 MVA 
  • Voltages up to 25KV

Longwall Electrics

Operators of the highest productivity longwall faces in the US trust IE longwall electrics to run their longwalls. Monorail and mule train designs, with ‘in-by’ XP controllers and mule trains measuring up to 10MVA, with built in starter cars. Wheeled or self-powered cat-tracked versions available. Fully integrated with PLC, automation, and communications.

  • Available in full configurations including XP controller and mule train
  • Multiple versions available for mobility, including wheeled, monorail, etc
  • Main transformers of 10MVA or more, with 5 KV starter car
  • Fully automated and custom PLC program developed by IE
  • IE handle MSHA approval process
  • Deep expertise in overhauls and rebuilds – have rebuilt half the LW electrics operating in the US
  • Up to 25KV primary, with 10MVA main transformer and 5KV starter circuits
  • MSHA approvals/RAMPs

Capacitor Banks

Ruggedized capacitor banks to help address voltage drop or power factor issues deep in the mine.  Incorporate all communications and controls, with common designs ranging from 200 -1500 KVAR.

  • Ruggedized mechanical design; low profile options available
  • Standard designs available up to 1500 KVAR.  
  • Integrated contactors and PLC for fully remote switching and controls
  • Up to 15KV
  • Up to 1500 KVAR/skid; 10,000 KVAR + through multiple skids


IE’s line of components – including MV and LV circuit breakers, ground fault relays and ground monitors, MV and LV connectors, capacitor trip devices, cable assemblies, and other devices – are setting the standard the quality, innovation, and productivity.  Contact us for more information.

  • Variety of circuit breakers, ground monitors/GFRs, connectors, and other devices, leverage technology from most recent decade.
  • 12 patents and counting
  • MSHA approved ground monitors and ground wire devices (only approved unit since 1985)
  • Drawout versions of multiple products
  • Product specific – go to our components page for more details

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