Buy Variable Frequency Drives Online in Australia
What is a variable frequency drive (VFD)?
A variable frequency drive (VFD) is an electronic motor controller that changes the speed of an AC induction motor by varying the frequency and voltage supplied to it. VFDs deliver soft starting, adjustable speed control, energy savings on variable-torque loads and built-in motor protection. AIMS Industrial supplies Invertek TECDriveAC and TTA series drives in single-phase and three-phase configurations across IP20, IP55 and IP66 enclosure ratings.
What is a VFD used for?
VFDs are used on pumps, fans, compressors, conveyors and mixers — any application where motor speed needs to vary or where the high starting current of direct-on-line starting must be avoided. On variable-torque loads like pumps and fans, VFDs can reduce energy consumption substantially compared with throttling or damper control.
How do you size a VFD?
Match the VFD's kilowatt rating to the motor's kilowatt rating and the supply voltage (single-phase 240V or three-phase 380-480V). For high-inertia or high-overload applications, the VFD is typically sized one frame above the motor. Confirm the enclosure IP rating matches the installation environment — IP66 is required for direct outdoor or washdown use.
VFD Selection — Quick Reference (Invertek Range)
Variable Frequency Drives (VFDs) control AC induction motor speed via PWM output. Selection turns on supply voltage (single 240V vs three-phase 415V), motor kW rating, enclosure protection (IP rating), and whether a built-in isolator is needed for safe maintenance.
| VFD Model | Input Supply | IP Rating | Best For |
|---|---|---|---|
| TECDriveAC — Single Phase 240V Input | 1Ph 240V → 3Ph motor output | IP20 (panel mount) | Domestic/light commercial supply running 3-phase motor — workshop default |
| TECDriveAC — 3Ph 380-480V IP20 | 3Ph 415V | IP20 (panel mount) | Switchboard install — protected indoor environment |
| TECDriveAC E3 — IP66 | 3Ph 380-480V | IP66 (sealed) | DIRECT MOTOR MOUNT — no enclosure needed, outdoor + washdown |
| TTA P2 — IP55 | 3Ph 380-480V | IP55 (dust/water resistant) | Industrial environments, moderate exposure |
| TTA E3 — IP66 + Switched | 3Ph 380-480V | IP66 (sealed) | Harsh industrial, washdown, integrated mains isolator for safe maintenance |
Energy savings: 20–50% typical on variable-torque loads (pumps, fans) per the Affinity Laws (power varies with cube of speed). Soft start: dramatically reduces starting current vs DOL (Direct On Line), protects motor + electrical infrastructure. Sizing: match VFD kW ≥ motor kW; for high-inertia or high-overload, oversize by 1 frame. Applications: pumps, fans, compressors, conveyors, mixers. Companion: electric motors, Invertek brand range, electric motor guide.
Variable Frequency Drives (VFDs)
AIMS Industrial supplies Invertek variable frequency drives for controlling the speed of AC induction motors in industrial and commercial applications. VFDs deliver energy savings, smooth motor starting, adjustable speed control and motor protection in a compact, reliable package.
TECDriveAC Series
The TECDriveAC range covers single phase 240V input (for single phase supply environments) and three phase 380–480V input configurations. Available in IP20 (panel mount) and IP66 (sealed enclosure) protection ratings, suiting indoor switchboard installations through to outdoor and wash-down environments. The E3 IP66 version allows direct motor-mounting without a separate enclosure.
TTA Series
The TTA series provides three phase 380–480V drives in P2 IP55 and E3 IP66 configurations with both switched and non-switched options. The robust IP66 enclosure is rated for harsh industrial environments including dust, moisture and hose-down cleaning. Switched variants integrate a mains isolator for safe maintenance without additional switchgear.
Applications
VFDs are used across pumps, fans, compressors, conveyor drives, mixers and any application where motor speed control or soft starting is required. Starting current is dramatically reduced compared to direct-on-line starting, which protects both equipment and electrical infrastructure. Energy savings of 20–50% are typical in variable-torque applications such as pumps and fans.
Buying Guide
Match the VFD to your motor's kW rating and supply voltage. Ensure the enclosure IP rating suits the installation environment. For applications in dirty or wet locations, IP66 drives eliminate the need for a separate control panel enclosure. Contact our team for sizing and compatibility assistance.
Where Australian industry uses VFDs
Variable Frequency Drives are the default motor controller for any industrial process where speed needs to change, soft starting matters, or energy savings on partial-load operation pay for the hardware. Australian industries that drive most VFD demand include water and wastewater (pump stations and treatment plant aerators where flow varies by demand), HVAC and building services (fan and pump speed matching to load delivers the headline energy savings), food and beverage processing (conveyor speed control, mixing and pumping with sanitation washdown environments), mining and resources (dust extraction fans, slurry pumps, conveyors with high-inertia starts), and general manufacturing (process pumps, fans and compressors). The compelling case is energy — for centrifugal pumps and fans driven by an unchanging line-frequency motor running into a throttling valve or damper, fitting a VFD and modulating motor speed instead can cut the input power by 30–50% at typical part-load operating points. The mechanical wear reduction on belts, couplings and bearings from soft starting is the second pay-back.
Australian electrical standards that apply to VFD installations
VFDs feed pulse-width-modulated voltage to the motor and draw harmonic currents from the supply, so they sit in a regulated installation envelope. AS/NZS 3000 (the Wiring Rules) is the head standard for any electrical installation in Australia and applies to the VFD's incoming supply, switchgear, motor cable, earthing and protection. AS/NZS 3008 covers cable selection — VFD output cables need to be sized for thermal rating and screened against radiated emission depending on cable run length. AS/NZS CISPR 11 covers electromagnetic compatibility (EMC) emissions for industrial drives; most quality VFDs in our range carry CISPR 11 Class A or Class B EMC filtering built in to comply with this. AS/NZS 61800.3 covers adjustable-speed electrical power drive systems specifically and is the standard a switchboard builder will reference when integrating the drive. Installation work on a VFD is electrical work — only a licensed electrician can connect supply and motor cables, configure the drive parameters, and commission the installation.
How to specify a VFD — kW, voltage, IP rating, control
Sizing is straightforward when you know the motor data plate. Match the VFD continuous kW rating to the motor shaft kW for variable-torque loads (pumps, fans) and one size up for constant-torque loads (conveyors, mixers, hoists) where start current and overload demand are higher. Supply voltage choices are single-phase 240V input (small drives up to about 2.2kW for residential and light commercial), three-phase 415V input (the default for any industrial drive above 2.2kW), and 690V for large mining and heavy industry drives. Enclosure IP rating drives the installation cost — IP20 drives sit in a switchboard enclosure where the panel provides the environmental seal, IP55 drives wall-mount in protected industrial spaces, and IP66 drives mount in washdown, dusty or outdoor environments without a separate enclosure (the right choice for food and beverage washdown, dust extraction fans and external pump stations because they eliminate the panel cost and the heat-soak issue).
Control interface choices include local keypad (built into the drive face), digital inputs from external switches and PLC, analogue inputs from process transmitters (4–20mA pressure transducer driving a constant-pressure pump system is the classic example), and fieldbus communication (Modbus RTU is the universal industrial standard; Ethernet/IP, Profinet and BACnet sit above for HVAC and process integration). Specify the communication protocol up-front — adding it later means a different drive.
Invertek VFD range at AIMS
AIMS Industrial supplies the Invertek Optidrive range — UK-designed drives manufactured to international quality standards with strong Australian technical support and parts availability. The Optidrive E3, P2 and TECDriveAC families cover the practical industrial range from sub-1kW single-phase washdown pumps through to 250kW+ three-phase process drives. Why Invertek over the alternatives: the configuration interface is straightforward (the drives can be set up in under five minutes from the keypad without specialist software), the EMC filtering is built in across the range, the IP66 outdoor and washdown variants are price-competitive against IP20 plus separate enclosure, and the Australian parts pipeline means a failed drive can be replaced or repaired without waiting for international shipping.
Specific Invertek families AIMS stocks: Optidrive E3 — compact general-purpose drives for fans, pumps and conveyors up to 22kW; Optidrive P2 — premium drives with advanced control (sensorless vector and closed-loop options) for demanding applications up to 250kW; TECDriveAC — economy series for OEM and budget-constrained applications where the load is predictable; IP66 outdoor — fully sealed variants for pump stations, irrigation, washdown and outdoor installations.
VFDs pair with what else at AIMS
A VFD is half of a drive package. The other half is the motor. AIMS supplies three-phase electric motors from TechTop in IE2 and IE3 efficiency ratings, in sizes that match the Invertek drive range exactly. For applications that need a brake — overhead doors, hoists, conveyors with positional accuracy — see brake motors. Pair with appropriate couplings for the driven equipment, and add anti-vibration mounts to the motor base where mounting rigidity is suboptimal. For the broader power transmission scope, see bearings and power transmission.
VFDs — common questions
Does fitting a VFD really save energy on a centrifugal pump?
Yes, but the savings only materialise when the load actually varies. For a centrifugal pump running at fixed full-load output into an open system 24/7, a VFD adds the drive's own conversion losses (typically 2–5%) and saves nothing. For a pump that throttles or runs intermittently, the cube law on centrifugal output means that a small speed reduction delivers a large energy reduction — running at 80% speed delivers about 51% of the input power. The pay-back assessment needs the actual operating profile across a typical week, not the rated full-load number.
Can a VFD power a motor over a long cable run?
Yes, but the practical limit depends on the cable type and the drive's output filter. PWM voltage from the drive output reflects off cable impedance discontinuities and the motor terminal, producing voltage overshoots that can damage motor insulation. Standard unshielded cable runs above about 30 metres need either a screened VFD cable (the recommended approach), an output choke at the drive, or a du/dt filter for very long runs. AS/NZS 3008 cable thermal sizing applies as the baseline; the EMC and voltage-overshoot considerations apply on top.
What's the difference between IP20, IP55 and IP66 drives?
IP20 drives are open-frame and need to sit inside a switchboard or control panel enclosure to meet the installation environmental rating. IP55 drives have built-in dust and limited splash protection — they suit protected industrial spaces but not direct washdown or outdoor weather. IP66 drives are dust-tight and pressure-jet protected — they're the right choice for food and beverage washdown, exterior pump stations, dust extraction fans, and any installation where a separate enclosure adds cost and traps drive heat against the electronics.
Can I use a VFD on a single-phase motor?
Generally no. Single-phase induction motors with capacitor-start or capacitor-run circuits don't respond to PWM frequency control because the capacitor circuit is tuned to line frequency. The common solution where speed control is needed on a single-phase supply is to use a single-phase-input / three-phase-output VFD driving a small three-phase motor — Invertek's single-phase input drives in the sub-3kW range are designed for exactly this scenario and they work well for small pumps, fans and conveyors.
What about VFDs for hoists, lifts and cranes?
Lifting applications need closed-loop vector control (or sensorless vector with appropriate parameter setup) plus a dynamic braking resistor on the drive's DC bus to dissipate regenerative energy when the load lowers. Standard general-purpose drives without braking resistors will trip on overvoltage when a heavy load descends. Specify a vector-capable drive and check the braking resistor sizing against the lifting application's regenerative duty.
Need sizing help, EMC advice or a paired motor-and-drive package quote? Contact our team for sizing and compatibility assistance.
People Also Ask — Variable Frequency Drives (VFDs)
Q: What is a Variable Frequency Drive?
A Variable Frequency Drive (VFD) is an electronic controller that varies the frequency of AC power supplied to an electric motor, changing the motor's speed. Used to: control speed of fans, pumps, conveyors; provide soft-start (avoid in-rush current at startup); save energy (running motors at the load-matching speed); enable variable-flow processes. Common in workshops, manufacturing, HVAC, and any application where fixed-speed motors waste energy or cause process issues.
Q: When do I install a VFD?
Centrifugal pump or fan running at constant speed but variable load: VFD saves 30-50% energy by matching speed to load. Conveyor with variable feed rate: VFD provides flow control. Motor that draws excessive starting current (DOL or star-delta): VFD provides soft-start. Process control requiring variable speed (winding, mixing, dosing): VFD enables setpoint control. Don't install VFDs unnecessarily — for constant-speed constant-load applications, the VFD cost isn't recovered.
Q: What size VFD do I need?
Match VFD output current capability to motor full-load current (FLC). Typical sizing: VFD rated current ≥ motor FLC × 1.0 (general purpose). For high-overload applications (positive displacement pumps, conveyors with shock load): VFD rated current ≥ motor FLC × 1.25-1.5. Voltage match: 415V three-phase for most industrial; 240V single-phase to three-phase VFDs for workshop applications with single-phase supply. Always check VFD voltage and current ratings against motor nameplate.
Q: VFD vs soft-starter — what's the difference?
Soft-starter: reduces starting current at motor start, no speed control during operation, lower cost. Suitable when soft-start is all that's needed. VFD: controls speed during operation AND provides soft-start. Higher cost but more functionality. For pumps and fans where speed control gives energy savings: VFD pays back. For motors where only the start matters (large compressors, conveyors): soft-starter is sufficient and more cost-effective.
Q: Are VFDs noisy and EMC-compliant?
Modern VFDs produce switching frequencies typically 4-16 kHz — can cause audible whine in motors (mitigation: higher switching frequency setting). EMC (Electromagnetic Compatibility) compliance per AS/NZS CISPR 11 requires input filters and shielded motor cables to prevent radiated emissions. Most quality VFDs include EMC filters as standard. For installations near sensitive electronics, additional filtering may be required. Always specify EMC-compliant VFDs for any industrial installation.