Vector control: when you really need it and when V/f is fine
Customers buy vector VFDs from us for two reasons. One: hold full torque at very low speeds (1-3 Hz) for hoists, lifts, crane gear, accurate conveyor metering. Two: fast reaction to load changes on winders, extruders, presses. If your job is just a pump or a fan, vector control is overspend: scalar V/f covers it. We ask the customer what is actually turning and tell them straight: take AC10 V/f, do not overpay.
Which series we ship as the main vector workhorses
From our 2025-2026 Kyiv stock: Veichi AC310 with sensorless SVC holds 150% torque at 0.5 Hz, range 0.75-630 kW; INVT GD200A with FOC and an optional PG card for encoder feedback (mandatory on lifts and high-precision feeds); Delta VFD-C2000 with motor auto-tuning; Schneider ATV320/ATV930 with DTC and STO for Safety-rated jobs. We add Mitsubishi FR-A800 when the project already runs a Japanese CNC.
What we ask before ordering. One: do you need encoder feedback (PG card, FOC closed-loop). It is mandatory on lifts, cranes, and high-precision feeds. Two: do you need STO (Safe Torque Off) to meet EN 61800-5-2, for that we have ATV320/930, GD350A, AC310 SafeFunc. Three: motor auto-tune. We recommend running the full RT test before going live, otherwise vector algorithms behave like V/f at a higher price.
Top-selling Veichi AC310 models (sales over 12 months)
| Model | Power | Current, A | Supply | Application |
|---|---|---|---|---|
| AC310-T3-004G/5R5P-B | 4.0 kW | 10 | 3×380V | Conveyors, mixers, compressors |
| AC310-T3-1R5G/2R2P-B | 1.5 kW | 4 | 3×380V | Small machines, gate automation |
| AC310-T3-5R5G/7R5P-B | 5.5 kW | 13 | 3×380V | Winding machines, extruders |
| AC310-T3-7R5G/011P-B | 7.5 kW | 17 | 3×380V | Elevators, overhead cranes |
| AC310-T3-2R2G-B | 2.2 kW | 6 | 3×380V | Industrial pumps, crushers |
Vector vs scalar control — when to use which
| Parameter | Vector (AC310 SVC/FVC) | Scalar (V/f) |
|---|---|---|
| Torque at 0 Hz | 100% rated | 40-60% |
| Speed accuracy | ±0.5% (SVC), ±0.01% (FVC) | ±3-5% |
| Starting torque | 150% at 0.5 Hz | 100% at 5 Hz |
| Response time | < 20 ms | 100-200 ms |
| Typical use | Cranes, elevators, extruders | Pumps, fans |
Manufacturers and series
Veichi — the AC310 series is the main vector drive in our catalog. It supports sensorless vector control (SVC), closed-loop vector with encoder (FVC), built-in PLC (up to 10,000 steps), braking module, and RS-485 Modbus RTU port.
By power rating
AC310 vector VFDs are available in: 2.2 kW, 3 kW, 5.5 kW, 7.5 kW, 11 kW, 15 kW, 22 kW and above.
By power supply
Single-phase models (1×220V): 0.75 to 5.5 kW — for single-phase to three-phase conversion. Three-phase (3×380V): 0.75 to 560 kW — full industrial range.
Warranty and support
Official 24-month warranty. Delivery across Ukraine: Nova Poshta, Ukrposhta. Pickup from Lviv warehouse. Free engineer consultation on power selection and control mode.
