FF1 – Fans & Pumps VFD Control Panel

By Yin on 11th Sep 2014

What is a FF1?

The FF1 is a variable frequency drive control panel (also known as VFD in a box, VFD enclosure, or motor control panel) that is manufactured by Motor Drives International. Along with its siblings - SV1 & F3R, each are designed for different environments and applications. The FF1 is very popular for a variety of industrial applications including fans and pumps. It has a NEMA 1 type enclosure, and houses VFDs ranging from 5HP to 800HP (for higher horse powers, MDI manufactures Custom Panels that will meet specific needs).

Some of the features of FF1 include: easily changeable air filter, LED lights showing real-time status of the panel, an advanced numeric keypad, remote I/O capability, operator devices, and pad-lockable through door circuit breaker disconnect handle. Optional add-ons include: 3% or 5% line reactors, 12% or 15% harmonic filter system, 3 contactor bypass, and many more.

Differences between SV1, FF1, F3R

The FF1 family (Left: 48"x35", Middle: 36"x24", Right: 60"x36")

The inside view of the 36"x24" FF1 with a 15% harmonic filter (optional), 3 contactor bypass and a circuit breaker disconnect

The Inside view of the 60"x36" FF1 with a DC link choke, 3% line reactor, 3 contactor bypass, and a circuit breaker disconnect

Gray: Mitsubishi F700 VFD (standard equipment)
Orange: DC link choke (Comes with Mitsubishi F-series 180+ Amps VFDs)

Circuit breaker disconnect - shuts off the power before you open the panel

Redundant fan to ensure the temperature stays cool

Air filter located outside of the panel - change it without opening panel door or shutting off power

Mitsubishi advance numeric keypad that will make programming much quicker

LED lights to show real-time status of the VFD panel

Padlock-able door handle

The 3 contactor bypass, and part of the 3% line reactor (orange)

Left: An inside view of a 208V FF1. You can see the 3 capacitors - the silver cylinders in the middle.
Right: The rear side of the 60"x36" FF1. The VFD comes out in the back for ventilation purpose in all 60" FF1


  • Great for fan and pump applications
  • 3 enclosure sizes available
  • NEMA 1 gray enclosure
  • Filtered forced air ventilation
  • Redundant cooling fans for backup
  • Easily removable pleated air filter placed outside of the enclosure for easy removal and replacement without cutting power or opening the enclosure door
  • All components housed in one single enclosure, no additional wiring or boxes
  • Easy installation
  • 3 lines in & 3 lines out
  • UL508A listed
  • Remote I/O capability
  • Two optional cards can be installed simultaneously
  • Soft PWM for peak voltage mitigation at motor terminals and quiet operation
  • Advanced full numeric keypad installed in the front of the panel - operate & maintain without opening the panel or cutting power
  • 3% (Standard) or 5% (Optional) line reactors are available to limit harmonic distortion to 35% or 27% respectively
  • 12% (Optional) or 15% (Optional) harmonic filter available to limit harmonic distortion to 12% or 15% respectively
  • Three contactor bypass (optional) electrically and mechanically interlocked, allows the motor to run across the line in case of a VFD failure
  • Door-interlocked input circuit breaker disconnect - provides additional safety by powering down the equipment before opening the panel and allowing OHSA lockout
  • Embossed numbering system - each wire is uniquely identified for ease of troubleshooting
  • 22mm door operator switches - power on and off and make adjustments without opening the panel


  • Available from 5 to 75HP (230V) or 5 to 800HP (460V)
  • Frequency: 50 or 60Hz
  • Overload rating: 110% for 60 seconds, 120% for 3 seconds (additional overload ratings optional)
  • Standard equipment: Mitsubishi F700 series VFD (other options available)
  • Standard ambient operating temperature: 40° C
  • 1 year standard warranty (extended warranties optional)

Shop our FF1 VFD panels now:

Also check out the other two MDI panel series:

SV1 (NEMA 1 panel – popular for HVAC application)
F3R (NEMA 3R outdoor panel)