Applications for Variable Frequency Drives

Please see the chart below to select which power rating your application falls under: Light, Normal or Heavy Duty. Hours of operation per day, elevation and the type of application can affect your VFD selection. For example, a 15hp AC Motor used in a plastic extruder would require a higher rated VFD than the same 15hp AC motor used in a hosting winch application.

Waste Water

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Concentrator (central drive)	Light	Light	Normal
Filter presses	Light	Normal	Normal
Vacuum filter	Light	Normal	Normal
Flocculation agitator	Light	Light	Normal
Aerator	Heavy	Heavy	Heavy
Circular aerator	-	Normal	Heavy
Brush aerator	-	-	Heavy
Screening plant	Light	Light	Normal
Circular and longitudinal scrapers	Light	Normal	Normal
Collectors	Light	Light	Normal
Sludge Collectors	Light	Light	Normal
Pre-concentrator	-	Light	Normal
Sludge compressor	Normal	Normal	Normal
Achimedian screw water pumps	Light	Light	Normal
Water turbines	-	-	Heavy
Settling tanks	Light	Light	Light
Chemical substance loaders	Light	Light	Normal
Dehydration screens	Normal	Normal	Normal
Slag crushers	Normal	Normal	Normal
Slow or fast mixers	Normal	Normal	Normal
Bucket Wheels
Impeller pumps	Light	Normal	Normal
Displacement pumps 1 piston	Normal	Normal	Heavy
Displacement pumps > 1 Piston	Light	Normal	Normal

Excavators

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Bucket chain	-	Normal	Normal
Tippers	-	Normal	Normal
Tracklaying vehicles	Light	Normal	Heavy
Bucket Wheels
as pick-ups	-	Normal	Normal
for original material	-	Heavy	Heavy
cutting heads	-	Heavy	Heavy
slewing gear*	-	Normal	Heavy
Bucket Wheels
Conveyers	Light	Normal	Normal
Cutting head drives	Normal	Normal	Normal
screens	Normal	Normal	Normal
stackers	Light	Light	Normal
hoisting winches	Light	Light	Normal

Mining

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Crushers	Normal	Normal	Heavy
Vibrators and screens	Normal	Normal	Heavy
Slewing gear	-	Normal	Heavy
Bucket Wheels
Grinding machine for sand	Light	Light	Normal
Hammer mills	Normal	Normal	Heavy

Chemical Industry

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Bucket Wheels
Extruders (plastics)	-	Normal	Normal
Extruders /w variable speed	Normal	Normal	Normal
Extruders /w fixed speed	Normal	Normal	Normal
Batch kneaders	Normal	Normal	Normal
Continuous mixers	Normal	Normal	Normal
Mixing plant	Light	Light	Light
Calendars	Normal	Normal	Normal
Blower units	Normal	Normal	Normal
Coating	Light	Light	Light
Films	Light	Light	Light
Pre-shedder	Normal	Normal	Normal
Bars	Light	Light	Light
Sheets	Light	Light	Light
Tubes	Light	Light	Normal
Bucket Wheels
Extruders (rubber)	-	Normal	Heavy
Rubber kneader	-	Heavy	Heavy
Continous mixers	Normal	Normal	Normal
Refiners - two-cylindar	Normal	Normal	Normal
rubber rollers (2 in series)	Normal	Normal	Heavy
rubber rollers (3 in series)	-	Normal	Heavy
Heating rollers	Normal	Normal	Normal
Rubber calenders	-	Normal	Normal
Calenders	-	Normal	Normal
Cooling Drums	-	Normal	Normal
Mills	Normal	Normal	Heavy
Sheet rollers	Normal	Normal	Heavy
Refining rollers	Normal	Normal	Heavy
Bucket Wheels
for homogeneous material	-	Normal	Normal
for inhomogeneous material	Normal	Normal	Normal
Bucket Wheels
with uniform density	Light	Normal	Normal
with varying density	Light	Normal	Normal
with uneven gassing	Normal	Normal	Heavy
Toasters	Light	Normal	Normal
Centrifuges	Light	Light	Normal

Iron Smelting Metal Production and Processing

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Sheet turning device	Light	Light	Light
Block press	Light	Light	Light
Reelers	-	Normal	Normal
Cooling bed scrapers	-	Normal	Normal
sheet pusher	Normal	Normal	Normal
Winders / Coilng machines	-	Normal	Heavy
Cutting rollers	Normal	Normal	Normal
Wire-pulling machines	Normal	Normal	Heavy
sheet metal bending machines*	-	Light	Light
Bucket Wheels
Roller conveyors - continuous	-	Normal	Normal
Roller conveyors - intermittent	-	Heavy	Heavy
Tube reversing	-	Heavy	Heavy
Bucket Wheels
General	Heavy	Heavy	Heavy
Continuous cutting*	-	Normal	Normal
Cranked cutting*	Light	Light	Light
Continuous casting drivers*	-	Normal	Normal

Rollers

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Sheet metal reversing	-	Call	Call
Sheet slab reversing	-	Call	Call
Wire reversing	-	Heavy	Heavy
Thin sheet metal reversing	-	Heavy	Heavy
Thick sheet metal reversing	-	Heavy	Heavy
Roller adjusters	Light	Light	-

Energy

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Frequency converters	-	Heavy	Heavy
Water wheels	-	-	Normal
Water turbines	-	-	Heavy
Electricity generators	Light	Light	Light

Conveyor Plant

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Bucket conveyors	-	Normal	Normal
Bucket conveyors /w centrifugal emptying	Light	Light	Light
Conveyor reels	Normal	Normal	Normal
Bucket Wheels
Plate feeder	Light	Light	Normal
Belt feeder	Light	Light	Light
Table feeder	Light	Light	Light
Swivelling loader	Normal	Heavy	Heavy
Helical loader	Light	Normal	Heavy
Conveyors /w evenly distributed load	Light	Light	Light
Conveyors Heavy duty	Light	Normal	Normal
Conveyors /w unevenly distrubted load	Light	Normal	Normal
Belt conveyors = 100kW	Light	Light	Normal
Belt conveyors >100kW	Light	Normal	Normal
Goods lifts	-	Light	Normal
Vertical conveyors - other	-	Normal	Heavy
Passenger lifts*	-	Normal	Normal
Slat conveyors	-	Light	Normal
Vibrators and screens	Normal	Heavy	Heavy
Swinging or vibrating conveyors	Normal	Heavy	Heavy
Escalators	Light	Normal	Normal
Rail vehicles	-	Normal	-
Bucket Wheels
Loading	Light	Normal	Normal
Gravity emptying	Light	Light	Light
Bucket Wheels
Heavy Duty	Normal	Normal	Heavy
Medium Duty	Light	Normal	Normal
Inclined lifts	Light	Normal	Normal

Wood Industry

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Bucket Wheels
Debarking macines - spindle feed	Light	Normal	Normal
Main drive	Normal	Normal	Heavy
Conveyors - Burners	Light	Light	Normal
Main or heavy duty	Normal	Normal	Normal
Main trunk	Normal	Heavy	Heavy
Sawing, carousel	Light	Light	Normal
Bucket Wheels
Plate	Normal	Heavy	Heavy
Transfer	Light	Normal	Normal
Bucket Wheels
Floor	Normal	Normal	Normal
Green wood	Normal	Normal	Heavy
Bucket Wheels
Chain	Normal	Normal	Normal
Work driver	Normal	Normal	Normal
Paring Cylinder	Normal	Heavy	Heavy
Bucket Wheels
Trimming machine	Light	Normal	Normal
Multiple blades	Normal	Normal	Normal
Cutter	Light	Light	Normal
Stacked trunks	Normal	Normal	Normal
Trunk conveyor - ramp with wheels	Normal	Normal	Normal
Trunk tipping device	Normal	Normal	Normal
Paning machine feed	Light	Normal	Normal
Trunk tipping roller trains	Normal	Normal	Normal
with rollers	Light	Light	Normal
Selection table	Light	Normal	Normal
Roller train with tilting table	Normal	Normal	Normal
Bucket Wheels
Chain	Normal	Normal	Normal
Track	Normal	Normal	Heavy
Plate drive	Light	Light	Normal
Drives for veneer turning machines	Light	Light	Normal

Compactors

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Compactors	Heavy	Heavy	Heavy

Cranes***

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Bucket Wheels
Slewing gear*	Light	Normal	Normal
Derricking gear	Light	Light	Normal
Bridge trolleys for portal cranes	Call	Call	Call
Bridge trolleys for portal cranes	Normal	Normal	Heavy
Lifting gear	Light	Light	Normal
Luffing gear	Light	Light	Normal
Bucket Wheels
Main pulley system	Call	Call	Call
Auxilary pulley system	Call	Call	Call
Arm pulley systems	Call	Call	Call
Yaw drive	Call	Call	Call
Traveling drive	Call	Call	Call
Bucket Wheels
Main pulley system	Call	Call	Call
Auxiliary pulley system	Call	Call	Call
Bridge cranes	Call	Call	Call
Traveling drive for crane car	Call	Call	Call

Mills and Drums

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Cooling and drying drums	-	Normal	Normal
Rotary kilns	-	-	Heavy
Ball mills	-	-	Heavy
Coal mills	-	Normal	Normal
Bucket Wheels
Ball and rod mills	Heavy	Heavy	Heavy
Cylindrical ring gear	Heavy	Heavy	Heavy
Direct coupling	Heavy	Heavy	Heavy
Cement kilns	Normal	Normal	Normal
Dryers and coolers	Normal	Normal	Normal

Foodstuffs Industry

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Bucket Wheels
Sugar cane knives*	-	-	Normal
Sugar cane mills	-	-	Normal
Diced mash	-	-	Light
Extraction system, cooling machine, boiler	-	-	Normal
Beet washing, cutting machine	-	-	Normal
Beet peeling machine	Heavy	Heavy	Heavy
Oil mills	Normal	Normal	Normal
mills (low speed)	Normal	Normal	Heavy
Kneading machines	Light	Normal	Normal
Mincing machines	Light	Normal	Normal
Slicing machines	Light	Normal	Normal
Crushers and mills	-	-	Normal
Drying drums	-	Light	Normal

Paper Machines / Paper and Cellulose Industry

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
All types***	-	Heavy	Heavy
Bucket Wheels
Debarking drums and machines	Normal	Heavy	-
Rollers (pick-up, screen suction & screen feed)	-	Heavy	Heavy
Drying cylinders (roller bearings)	-	Heavy	Heavy
Calenders (roller bearings)	-	Heavy	Heavy
Filters (pressure and suction filters)	-	Heavy	Heavy
Chopping machines & shredders	Normal	Heavy	Heavy
Jordan mills	-	Normal	Heavy
Presses (bark, felt, gluing & suction presses	-	-	Normal
Rolling devices	-	-	Normal

Hydrapulpers

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Washing filters	-	-	Normal
Yankee cylinders (dryers)	Light	Light	Normal
Agitators (kneaders)	Normal	Normal	Normal
Agitators for pure liquor	Light	Light	Light
Paring cylinder	Heavy	Heavy	Heavy
Debarking machines (mechanical)	Heavy	Heavy	Heavy
Refiners	Normal	Normal	Normal
Paper Shredders	Light	Light	Light
Calenders	Light	Light	Light
Shredders	Heavy	Heavy	Heavy
Chip loaders	Normal	Normal	Normal
Patination cylinders	Light	Light	Light
Bucket Wheels
Chips, bark, chemicals	Light	Light	Light
Trunk (including table)	Heavy	Heavy	Heavy
Sleeve presses	Light	Light	Light
Millers	Heavy	Heavy	Heavy
Cylindrical tools	Light	Light	Light
Bucket Wheels
Paper machine	Light	Light
with conveyors	Light	Light	Light
Embossing machines	Light	Light	Light
Extrusion presses	Normal	Normal	Normal
pulp refiners	Normal	Normal	Normal
kiln drives	Normal	Normal	Normal
Paper rollers	Light	Light	Light
Plates	Normal	Normal	Normal
Presses - mat and suction	Light	Light	Light
Kneading machines	Heavy	Heavy	Heavy
Vacuum pumps	Normal	Normal	Normal
Flat reelers	Light	Light	Light
Bucket Wheels
Chips	Normal	Normal	Normal
Rotating screens	Normal	Normal	Normal
Vibrating screens	Heavy	Heavy	Heavy
Glue presses	Light	Light	Light
Super calender	Light	Light	Light
Concentrator (AC motor)	Normal	Normal	Normal
Concentrator (DC motor)	Light	Light	Light
Coiling and uncoiling holders	Normal	Normal	Normal
Surface rinsing machines	Light	Light	Light

Pumps

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
pumps	-	Normal	Normal
centrifugal pumps / impeller pumps	Light	Normal	Normal
Piston pumps (1 cylinder)	Normal	Normal	Heavy
Piston pumps (multiple cylinder)	Light	Normal	Normal
Archimedian pumps	-	Light	Normal
Rotary pumps (gear, vane, positive displacement rotary pumps)	-	-	Light

Agitators and Mixers

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Agitators for liquids	Light	Light	Normal
Agitators for liquids (/w suspended solids)	Light	Light	Normal
Agitators for liquids (variable density)	Light	Normal	Normal
Agitators for solid media (inhomogeneous materials)	Normal	Normal	Normal
Agitators for solid media (homogeneous materials)	-	Normal	Normal

Cable Railways

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Materials cableways	-	Normal	Normal
Pendulum cableways	-	Normal	Heavy
Ski tows	-	Normal	Normal
Circulating cableways	-	Normal	Normal

Screens

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Air Washers	Light	Light	Light
Rotary screen - stone or gravel	Light	Light	Normal
Mobile screens with water input	Light	Light	Light

Textile Machinery

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
General	Light	Light	Normal

Ventilators and Fans

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Centrifugal fans	Light	Light	Light
Pressure ventilated fans	Light	Light	Light
Push-pull counterflow fans	Normal	Normal	Normal
Industrial and mining fans	Normal	Normal	Normal
Blowers (axial and radial)	Normal	Normal	Normal
Centrifugal blowers	Light	Light	Light
Rotary blowers	Light	Light	Normal
Rotary vane blowers	Light	Light	Normal
Heat exchangers	Normal	Normal	Normal
Cooling tower fans	-	-	Normal
Dry cooling towers	-	-	Heavy
Wet cooling towers	Heavy	Heavy	Heavy

Compressors

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Piston compressors	-	Heavy	Heavy
Rotary compressors	-	Normal	Normal
Radial compressors	-	Normal	Normal
Screw compressors	-	Normal	Normal
Centrifugal comressors	Light	Light	Normal
Rotary vane compressors	Light	Light	Normal
Multi-cylinder reciprocating piston compressors	Normal	Normal	Normal
Single cylinder reciprocating piston compressors	Normal	Normal	Heavy

Cement Industry and Clay Processing

Application	Up to 5 Hours/Day	5-10 Hours/Day	Over 5-10 Hours/Day
Concrete mixers	Normal	Normal	Normal
Crushers*	Normal	Heavy	Heavy
Rotary Kilns	-	-	Heavy
Tube mills	-	-	Heavy
Separators	-	Normal	Normal
Rolling mills	-	-	Heavy
Brick presses	Normal	Heavy	Heavy
Tile presses	Normal	Heavy	Heavy
Kneading machines	Light	Normal	Normal