Variable Frequency Drive Systems and Controls

  • Do you have ac motors in your facility?
  • Do these motors need a variable output?
  • Do you use mechanical means to vary the output?

If you anwsered yes to these questions, you need to install variable frequency drives on these ac motors.
If you are not using VFD’s you are wasting energy and throwing money out the window.

Two Door Cabinet with ABB's NEW ACS 800 AC DriveIn the United States 50% of the total electrical energy generated is consumed by rotating equipment. 65% of this total is consumed by centrifugal or flow related applications such as fans, blowers, compressors, and pumps according to current estimates. Variable speed drive technology offers a cost-effective method to match driver speed to load demands and represents a state-of-the-art opportunity to reduce operating costs and improve overall productivity.

Joliet Technologies is an OEM that custom packages, integrates and engineers AC Variable Frequency Drives (VFD), DC Variable Speed Drives (VSD) and AC Drive Controllers. Our drive systems integrate top of the line manufacturers, like ABB, Emerson (Control Techniques & Saftronics / Fincor), Siemens and WEG to name a few. Our added value custom drive packages are built to your specifications for your application.

What is a Variable Frequency Drive?

You can divide the world of electronic motor drives into two categories: AC and DC, a motor drive controls the speed, torque, direction and resulting horsepower of a motor. AC drives control AC induction motors. DC drives typically controls a shunt wound DC motor, which has separate armature and field circuits.

Motor drives are also known as DC Drives, AC Drives, SCR Drives (Silicon Controlled Rectifier Drive), Variable Frequency Drives, Variable Speed Drives, Adjustable Speed Drives, Electric Motor Drives, Electronic Motor Drives, AC Motor Controllers, AC Inverters, Pulse Width Modulation (PWM) Drives and a few other names.

Which Drive is Right for your Application?

The AC Variable Frequency Drive market is huge, due to the great advances in highly reliable AC power electronics and high power microprocessors. The Flux Vector AC Drive for example, can compete on an application basis that DC Drives would in earlier years be required.

Variable Speed DC Drive.Even though AC Variable Frequency Drives are readily replacing DC Drives and motors, there is still a large base of DC equipment that has to be supported by experienced technicians. Joliet Technologies believes that by not abandoning the DC market we can better serve our customer base demands. For example, older machines with multiple exciting DC Analog drives and motors may be a great candidate for retrofitting newer digital DC drive equipment. Saving cost and down time.

If your needs are much simpler and speed control is not part of the work scope. Joliet Technologies can provide Custom AC Drive Controllers consisting of contactors, starters, relays, pushbuttons and PLCs. Our engineers can provide all PLC and Peripheral Programming needs. Panels can be designed by another OEM or we can help with engineering to specifications provided.

DC Variable Speed Drive
Torque control and limiting Brush life commutation maintenance.
Wide speed range (under 5000 RPM) Motor high speed limit (high speeds use expensive gear boxes)
Trimming capabilities Expensive large HP motors
Constant HP capabilities Power system harmonics
True 4-quadrant regenerative energy conversion NA
Few distance limitations NA
Cost (especially single phase sizes) NA
AC Variable Frequency Drive
Improved efficiency Distance limitations
Low motor maintenance Large system designs (high HP drive foot prints)
Tight control Cost (encoder feedback)
Digital control Expensive regenerative braking
High speed capabilities Power system harmonics
Reversing capability without extra power elements NA

Variable Speed Drive.Joliet Technologies Custom Panel Shop and On Site Retrofit Benefits

We have the experience and know how to provide you with the best drive for your application. Joliet Technologies can evaluate your current equipment and recommend either a Retro-Fit or System Replacement. Feel free to contact us with any drive questions you may have.

"Underwriters Laboratories Inc. (UL) is an independent,<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /> not-for-profit product safety testing and certification organization.<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /> UL has tested products for public safety for over a century.<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /> Each year more than 17 billion UL Marks are applied to products worldwide."<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /> "UL is not affiliated with Joliet Technologies and does not endorse the Web site." Joliet Technologies is a UL (Underwriters Laboratories) 508A Certified, Industrial Control Panels & Industrial Control Panels Certified for Canada shop.

Joliet Technologies is dedicated to provide the highest quality equipment and service. This is why we started this company. With our experience, expertise and commitment, you will be completely satisfied with our workmanship and our work ethic. All work is performed following our Quality Assurance System (based on the ISO9001:2008 Standard), assuring you the highest quality.

From system integration to panel fabrication Joliet Technologies provides quality systems and custom control panels for new applications or system upgrades, all in a timely fashion, and at competitive rates.

How to Maintain a VFD

Do you know how to maintain a VFD? Doing so is easier than you might think. By integrating some simple, logical steps into your preventative maintenance program, you can ensure your drives provide many years of trouble-free service.

RFQ – Request for Quoterequest4quote_200x100

  • If you have existing documentation of your specifications and application. Simply attached them to an e-mail to, it's that simple.
  • Or, if you have a single file that describes what you are looking for, simply upload that file, complete the required fields in the form below and Submit.
    File Upload:
  • Or, fill out this simple, No Obligation form (should only take a few minutes), and Joliet Technologies will send you a detailed quote for your equipment and application to your specifications.

* Required Fields

Your Information

Company Name *:

Phone Number *:

Email Address *:

Your Name *:

Quotation Required:

Drive Information

Describe Application:

Drive and (Motor) Type:

Incoming AC Voltage:

What atmosphere will the drive be installed in? (type of enclosure):

Operator Station:

Operator Functions and Indicators, (describe what control functions and indicators are required on the operator station):

Motor Information

HP (Horsepower):

FLA (Full Load Amps):

Speed Range:

Enclosure Type:

Tachometer Generator:

Motor Voltage (if AC):

Duty Cycle:


Would you like to be added to our email list? YesNo

Phone (815) 725-9696,
Toll Free (866) 492-9888,
Fax (815) 725-9393 or


Ask Joliet Technologies. Questions and/or Comments.Got a question or comment?
Need a Quote?
Contact Joliet Technologies to get the answers.

Print Friendly, PDF & Email