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The North American leader in power resistor products, Powerohm offers the broadest line of quality power resistors in the market place.   The Powerohm team is committed to providing the highest value, highest quality product at attractive prices.  Our engineering focus and dedication to the highest quality components and standards will result in the most effective resistor design for your application.

Neutral Grounding Resistors

Protect your equipment and personnel.  Powerohm’s neutral ground Resistors will limit fault current and reduce transient voltages to reduce damage and hazardous conditions during a fault.

High Resistance Grounding Systems

When your power system reliability is critical and down time is not an option Powerohm’s HRG is the solution for maximum system uptime.

  • Standard Off the Shelf Designs for System Voltage of 2,400 to 13,800
  • Time Ratings of 10,30, 60 Seconds as well as Extended and Continuous
  • Safety Enclosure in Finish Options (Painted. Mill Galvanized, Hot Dipped, SS and AL)
  • Entrance Bushings, CT’s, Elevating Stands, and Disconnect Switches.
  • Generator Grounding Systems with Grounding Transformer
  • Delta System Grounding with a  Zigzag Transformer
  • Seismic Qualified
  • Robust Electromechanical Control
  • Pulser for Quickly Locating a the Fault
  • Wall Mount and Floor Mount NEMA 1 and 3R Enclosures Options
  • Zigzag Transformers for Delta Systems
  • High and Low Voltage Designs
  • Optional Ammeter, Horn, Dual Set Point, Low Temperature Rise

DB Braking Resistors

Powerohm’s diverse braking options make it easy to find the right resistor for your dynamic braking application.  Regardless of your drive manufacturer Powerohm can provide for your braking requirements.

  • Catalog of Matched Resistors for Your Drive
  • For 230, 460, and 575 Volt Drives
  • 100% or 150% Braking Torque
  • Five Standard Duty Cycles
  • Custom Designs to Match Your Application
  • Convenient 2-Point Terminal Block for Easy connection
  • Temperature Switch Standard
  • Mill Galvanized Enclosure Standard

Braking Modules

Expertise in braking extends to Powerohm’s braking modules.  Designed with robust solid state components our braking modules will handle your most demanding applications.

  • Programmable Voltage
  • Highest Peak Voltage in Class
  • Highest Voltage Trip Point in Class
  • No Front End Bus Charge Required
  • Profibus and Ehernet Communications
  • Voltage Class 208-720 Volts

Load Banks

The right choice for your permanently mounted emergency power load testing.  Powerohm has manufactured load banks for over 10 years and now offers a standard off the shelf series of outdoor load banks complete with industry standard control features.  Our freestanding load banks feature a heavy gauge enclosure with galvanized steel powder coated finish to achieve a durable, long lasting finish.

  • Voltage Ratings of 208, 240, 480 and 600 volts.
  • Power Ratings Ranging from 200 kilowatts to 1000 kilowatts.
  • Heavy Duty Enclosure with Galvanized and Powder Coated Finish.
  • All Stainless Steel Load Elements and Exterior Fasteners.
  • Remote Control Panel in NEMA 12 Junction Box.
  • Multi-Compartment Enclosure Isolates Controls and Power Connections from Load Element and Blower Compartment.
  • Fused Circuit Protection for all Control and Power Circuits.
  • Industry Standard Malfunction and Safety Circuits.

Off-Highway Truck Resistors

High mechanical shock and vibration along with extreme environmental conditions drove Powerohm’s off-highway truck resistor design with focus on the importance of the resistor element and its reliability. The element design is critical and we consider our element superior to any other product available on the market. Powerohm Mining Resistors feature a continuous ribbon with no breaks or welds featuring a unique embossment pressed into the element that insures mechanical rigidity during extreme duty cycles. Powerohm has finally developed a mining resistor that is suitable for an extreme mining environment.

  • Powerohm designs feature a continuous folded ribbon with no welds.
  • Robust Stainless Steel Terminals are compressed and TIG welded.
  • Heavy Duty Framework withstands high vibration and shock.
  • Unique element embossment allows for superior strength and durability.
  • Non-breakable insulation exclusively used throughout the design

Transit Resistors

Based on our engineering experience, technical excellence and quality resistor designs, coupled with our  ISO 9001:2000 Quality Management System (includes both the design and manufacture), we believe we are the world’s best solution for quality transit resistor products.  Powerohm uses a large selection of resistor alloys, element styles and insulating media allow us to offer units that incorporate maximum reliability along with minimum overall weights and sizes. Powerohm offers custom coil, grid and ribbon assemblies specifically designed for use in transit applications such as light rail, trolley systems, electric buses, locomotive and heavy railways.   

Trapp Industrial Sales
Powerohm has built a reputation as one of the best values in the business. Our product and application knowledge allow us to provide exceptional sales assistance to help you select the best, most competitively priced products for your application.   Trapp Industrial Sales stand ready as your local expert to support you next resistor application.

Trapp Industrial Sales Engineers have the experience and the training to help you with all of your Powerohm product line applications.

Please visit the “Meet our Reps” page to find your local contact.