Class-leading low-harmonic VFD’s with revolutionary features such as ducted cooling and voltage-doubling.

3LH Series drives have an active switching input module that limits harmonic distortion on the power input. These drives are IEEE-519 compliant with no additional harmonic filters required. The active front end also provides the added benefit of power conditioning for the VFD. This allows the user to set and maintain output voltage even in the presence of weak utility voltage.

LH-series drives were designed specifically for the water well industry and provide features not found anywhere else. Configure a 3LH for your application with our product builder.

Superior Heat Rejection

Our innovative cooling design utilizes outside air in a compartment segregated from any sensitive electronics. This design eliminates the risk of contaminated air entering the electronics areas and ultimately prolongs the life and improves the efficiency of internal components.


Voltage Doubling

Significant Installation Cost Savings

Designed For Deep Set Wells
& Long Lead Applications

  • Eliminate the need for a costly transformer
  • Significantly reduce installation costs
  • Smaller motor cable & well size requirements
  • Voltage control for deep wells


3LH Model Comparison

Standard Features

3LHE Enterprise Chassis
Up to 50 Horsepower
3LHS Signature Chassis
Up to 200 Horsepower
3LH Performance Chassis
Up to 700 Horsepower
NEMA 3R Outdoor Enclosure

Large display, readable in direct sunlight

50°C (122°F) Rated
Ready to be exterior mounted, even in harsh climates


Up to 50 Horsepower

Up to 200 Horsepower

Up to 700 Horsepower

Optional Features

3LHE Enterprise Chassis
Up to 50 Horsepower
3LHS Signature Chassis
Up to 200 Horsepower
3LH Performance Chassis
Up to 700 Horsepower
Voltage Doubling

Panel Shop: Service Disconnect
Make maintenance easy and meet code without an external disconnect

Panel Shop: HOA Switch and/or Speed Pot

Panel Shop: Run and Fault Indicator Lights


Panel Shop: dV/dT Output Filter
Protect your motor, especially in long lead installs

Panel Shop: Sine Wave Output Filter
Protect your motor, especially in extra long lead installs

Panel Shop: Strikesorb Surge Protection
Multiple-hit protection, the best available

Panel Shop: System Bypass
Ensure constant uptime with a bypass, includes MCCB

Panel Shop: Pad Mount Leg Kit
Mount the VFD to a concrete pad

See the 3LH Enterprise See the 3LH Signature & Performance

1. Most models are 50°C (122°F) rated, some models may be 40°C rated.

2. Enterprise models are available with a Run or Fault light, but not both.

Our product builder will help you build and price a VFD for your application based on the horsepower of your pump.

Not sure? Contact our sales department and let us help you select the right variable frequency drive for your application.

Contact Us

Easy Setup

Perfect Pressure™ only requires a few minutes of setup time and is capable of controlling complicated constant pressure plumbing systems with ease and fewer instances of short cycling.

Read more about Perfect Pressure


Custom is usually associated with greatly increased cost and lead times, but not at Phase Technologies, custom is what we do. Learn how our UL 508A panel shop can help you stay on time and on budget.

Read about Phase UL 508A Panel Shop