VFD Variable Frequency Drive Pakistan Guide 2026 | CNC
VFD (Variable Frequency Drive) Pakistan — Complete Buyer's Guide 2026
Updated: May 2026 • CNC Electric Pakistan
VFD — Pakistan Quick Answer (2026)
A VFD (Variable Frequency Drive) — also called AC drive, inverter drive, or motor drive — controls the speed of a three-phase AC motor by varying the supply frequency (Hz) instead of voltage. In Pakistan, a 1.5 kW (2 HP) VFD starts around Rs.18,000, a 5.5 kW (7.5 HP) industrial unit is around Rs.55,000–75,000, and a 30 kW (40 HP) drive is Rs.180,000+. Most installs pay for themselves in 6–18 months through energy savings (typically 30–50% on pump and fan loads).
Already know your motor size? Browse the CNC VFD range → or message us on WhatsApp 0326-1111376 with your motor nameplate and we’ll recommend the right drive in 5 minutes.
What Is a VFD?
A Variable Frequency Drive is an electronic device that sits between the power supply and a three-phase induction motor. It takes incoming AC power, rectifies it to DC internally, and then re-creates a new AC waveform at whatever frequency you set — anywhere from a slow 5 Hz crawl up to 50 Hz (Pakistan standard) or beyond.
Because the speed of an AC induction motor is directly proportional to the supply frequency, controlling the Hz lets you control motor RPM precisely. The classic example is a water pump: instead of running it flat-out and throttling output with a valve, the VFD just runs the motor slower — saving a huge amount of power while delivering the exact flow you need.
When Do You Actually Need a VFD?
VFDs aren’t for every motor. They cost real money, so install one only where you get a clear payback. The four classic Pakistani use-cases are:
1. Water Pumps — Borehole, Booster, HVAC Chiller
A 5 HP borehole pump running 8 hours a day at full speed uses about 8,800 kWh/year. Slow it to 70% with a VFD when demand is low and you save 40%+ — roughly Rs.130,000 a year on a Pakistani industrial tariff. The VFD also eliminates water hammer and dramatically extends the pump’s mechanical life.
2. HVAC Fans — Air Handlers, Chiller Tower Fans, Exhaust
Fan power scales with the cube of speed. Drop fan RPM by 20% and you cut power by ~50%. Any facility with central AC, kitchen exhaust, or industrial ventilation will pay back a VFD on the biggest fan inside 9 months.
3. Conveyors, Mixers, Compressors — Process Control
Anywhere you need variable speed (slow start for a heavy mixer, ramp-up on a conveyor to avoid product slip, soft compressor starts), a VFD replaces gearboxes, hydraulic clutches, or dampers with simple electronic control.
4. Soft Start for Large Motors
Starting a 30 HP motor across-the-line draws 6–8x its rated current. That trips your MCCB, dims the lights, and stresses the motor windings. A VFD ramps the motor from 0–50 Hz smoothly over 5–30 seconds — no inrush, no nuisance trips, no mechanical shock.
VFD vs Soft Starter vs Star-Delta — Which Do You Need?
| Feature | VFD | Soft Starter | Star-Delta Starter |
|---|---|---|---|
| Variable speed control | Yes (full range) | No | No |
| Reduces inrush current | Yes (to 1x rated) | Yes (to ~3x) | Yes (to ~2x at start) |
| Energy savings on partial loads | 30–60% | None | None |
| Cost (5.5 kW Pakistan) | Rs.55,000–75,000 | Rs.30,000–45,000 | Rs.12,000–18,000 |
| Wiring complexity | Simple (in/out) | Simple | Complex (6 motor leads + 2 contactors + timer) |
| Best use case | Pumps, fans, conveyors | Constant-speed compressors | Legacy fixed-speed motors |
How to Size a VFD — Pakistan Quick Method
Sizing a VFD is mostly about matching the drive’s output amps to the motor’s full-load amps (FLA) on the nameplate. Pick the next VFD size up if you’re in between.
| Motor HP | Motor kW | Approx FLA (380V 3Φ) | VFD Size to Buy | Typical PKR Price 2026 |
|---|---|---|---|---|
| 1 HP | 0.75 kW | 2.0 A | 0.75–1.5 kW VFD | Rs.15,000–22,000 |
| 2 HP | 1.5 kW | 3.7 A | 1.5–2.2 kW VFD | Rs.18,000–28,000 |
| 3 HP | 2.2 kW | 5.0 A | 2.2–3.0 kW VFD | Rs.28,000–38,000 |
| 5 HP | 3.7 kW | 8.5 A | 3.7–4.0 kW VFD | Rs.38,000–48,000 |
| 7.5 HP | 5.5 kW | 12 A | 5.5 kW VFD | Rs.55,000–75,000 |
| 10 HP | 7.5 kW | 16 A | 7.5 kW VFD | Rs.75,000–95,000 |
| 15 HP | 11 kW | 23 A | 11 kW VFD | Rs.105,000–135,000 |
| 25 HP | 18.5 kW | 37 A | 18.5 kW VFD | Rs.150,000–195,000 |
| 40 HP | 30 kW | 60 A | 30 kW VFD | Rs.180,000–240,000 |
Wiring & Installation — The Three Cables That Matter
- Input power (L1/L2/L3): Take 3-phase 380V from a dedicated MCCB sized at 1.5x VFD nominal current. Add a line reactor if your supply has heavy switching loads on the same bus.
- Motor output (U/V/W): Use shielded VFD-rated cable from VFD output to motor terminals. Keep this run as short as possible — under 20 m for most drives, less for high-frequency carrier switching.
- Earth: Solid earth at both VFD chassis and motor frame. Never share earth with sensitive electronics — VFDs inject high-frequency leakage current that can confuse RCCBs on the same circuit.
VFD for Solar — Pakistan’s Newest Use Case
Pakistan’s rapid solar uptake (driven by NEPRA net metering) has created a new use case: solar-direct VFDs for agricultural pumping. These specialised drives accept DC input directly from PV strings, eliminate the inverter, and run a standard 3-phase irrigation pump straight off the solar array.
For agri-pump installs (typically 5–25 HP), solar VFDs deliver 100% of pumping needs through summer sunlight with zero grid dependency — perfect for off-grid borewells in Sindh, Punjab, and Balochistan. Pair the VFD with proper DC breakers and DC SPDs on the solar side.
Common Installation Mistakes in Pakistan
- Undersized input MCCB. A 5.5 kW VFD pulls 12 A at full load but draws spikes well above that during charging. Use the next standard size up — 25 A MCCB minimum.
- No input choke / EMC filter. Pakistan grids are noisy. Without a line choke, VFDs trip on overvoltage during WAPDA voltage swells.
- Mounting in sealed enclosures with no airflow. VFDs dissipate 3–5% of motor power as heat. A 7.5 kW drive in a sealed wall box will fail in months. Ventilate or use ambient-rated drives.
- Trying to switch motor on/off downstream. See the critical box above. Use the VFD’s digital inputs to start/stop instead.
- Ignoring carrier frequency for long cables. Default 4 kHz carrier with a 40 m motor cable produces voltage reflections that punch holes in motor windings. Either shorten the cable or fit dV/dt filters.
Frequently Asked Questions (FAQ)
What does VFD stand for?
VFD stands for Variable Frequency Drive. It is also called a variable speed drive (VSD), AC drive, inverter drive, or simply “motor drive” in everyday Pakistani trade usage.
Can a VFD run a single-phase motor?
No — standard VFDs only run three-phase induction motors. However, you can buy a VFD with a single-phase input and three-phase output, then connect it to a small three-phase motor. This is how many Pakistani workshops run small 3-phase machines on a regular domestic single-phase WAPDA connection.
How much can a VFD save on my electricity bill?
For pump and fan loads operating below 100% capacity, savings are typically 30–50%. A 7.5 kW pump running 10 hours/day at average 70% speed will save approximately Rs.18,000–30,000 per month on Pakistani industrial tariffs — paying back the VFD in 4–8 months.
Do I need a separate motor protection relay with a VFD?
No. The VFD has built-in motor overload, undervoltage, overcurrent, and over-temperature protection. You do still need input-side protection (MCCB) to protect the supply and the drive itself.
Will a VFD work on Pakistan’s unstable WAPDA supply?
Yes — quality VFDs accept input voltage from roughly 320 V to 460 V on a 380 V system and ride through brief sags. For very weak rural supplies, add an input line reactor and consider a voltage protector upstream to trip the supply during dangerous spikes.
Can I use a VFD with my generator?
Yes, but oversize the generator by 30–50% compared to the VFD nominal rating. VFDs draw a non-linear current waveform that creates harmonics — small gensets can sag or shut down under VFD load if undersized.
What is the price of a 5 HP VFD in Pakistan?
A 5 HP (3.7–4 kW) VFD in Pakistan costs approximately Rs.38,000–48,000 depending on brand and features. Industrial-grade VFDs with vector control, encoder feedback, and Modbus RTU sit at the higher end.
Need help sizing the right VFD?
Send us your motor nameplate (HP, kW, FLA, voltage) and application — we’ll recommend the right drive within 5 minutes.