Overview
The Delta VFD022B21A is a 2.2 kW (3 HP) compact variable-frequency drive from Delta's VFD-B series. It accepts single-phase 200–240V AC input and delivers three-phase PWM output to drive standard three-phase induction motors up to 11 A rated current.
The B-series fills the gap between Delta's entry-level L-series and the high-end C2000 line. It adds sensorless vector control for better speed regulation under changing load, a built-in PLC function block with 16 preset speeds, and a PID feedback controller — capabilities you would normally reach for a larger, more expensive drive for. The compact footprint (150 x 260 x 160.2 mm) fits control panels where depth is constrained.
This drive sees service across a wide range of general-purpose industrial applications: HVAC fan and pump speed control, small conveyors and packaging lines, woodworking machinery, textile equipment, air compressors, and centrifugal loads. It is also a known OEM replacement for Jet milling machine spindle drives (models JTM949EVS-F08 and similar).
Key Specifications
| Parameter | Value |
|---|---|
| Rated motor power | 2.2 kW / 3 HP (constant torque); 3.7 kW / 5 HP (variable torque) |
| Input | 1-phase 200–240 V AC, 50/60 Hz |
| Output | 3-phase 0–240 V AC |
| Rated output current | 11 A |
| Output frequency range | 0.1–400 Hz |
| Control modes | V/F, sensorless vector control (SVC) |
| Overload capacity | 150% rated current for 60 seconds |
| Starting torque | 150% at 1 Hz (sensorless vector mode) |
| Built-in braking transistor | Yes (external braking resistor supported on B1/B2 terminals) |
| Communication | RS-485 Modbus RTU, up to 38,400 bps |
| Enclosure | IP20 / NEMA 1 |
| Dimensions (W x H x D) | 150 x 260 x 160.2 mm |
| Weight | 4.5 kg |
| Operating temperature | -10 to +40 °C |
Onboard Features Worth Knowing
16 preset speeds. Step through fixed frequencies via digital input terminals — no PLC needed. Useful for multi-stage pump sequencing, simple positioning, or conveyor speed selection by operator switch.
Built-in PID controller. Closed-loop control with feedback wired directly to the VFD's analog input (4–20 mA or 0–10V). A common use case: maintain constant water pressure — wire a pressure transducer to AVI, set the PID setpoint, and let the drive modulate motor speed automatically.
Auto torque compensation. Raises output voltage at low frequencies to maintain torque. This matters on conveyors, crushers, and extruders where breakaway friction at startup is high.
Auto tuning. Measures the connected motor's stator resistance and no-load current. Run this once after wiring the motor; it measurably improves low-speed torque accuracy and reduces current hunting in sensorless vector mode.
4-step accel/decel ramps. Program independent acceleration and deceleration times for different frequency bands. Prevents mechanical shock when a high-inertia load crosses a resonant speed range.
Skip frequencies. Define up to three frequency windows the drive jumps past to avoid mechanical resonance. If your fan housing vibrates at 32 Hz, set a skip band from 30–34 Hz and the drive will accelerate straight through it.
Heatsink over-temperature detection. The drive monitors its own heatsink temperature and issues a warning before hitting the thermal trip threshold — giving you time to check cabinet ventilation rather than dealing with an unplanned stop.
Selection & Installation Notes
Why single-phase input matters. Many smaller workshops, remote pump stations, and agricultural installations only have single-phase 230V service. The VFD022B21A converts single-phase input to three-phase output internally — no rotary phase converter needed. Size the input wiring for the higher single-phase line current, which runs roughly 1.73× the equivalent three-phase draw.
VFD022B21A vs. VFD022B21B. The "A" variant ships with a fixed 7-segment LED keypad. The "B" variant usually comes with the detachable LCD keypad (VFD-PU01) and may carry slightly different default parameter values. Electrically, the two are identical — same power stage, same ratings, same terminal layout. If you already have a PU01 keypad from another drive, the "A" variant saves you the cost of a second one.
B-series vs. other Delta series. For a simple fan or pump that only needs V/F control, Delta's L-series or the compact EL-series will do the job at a lower price point. Step up to the B-series when you need sensorless vector mode (speed holding accuracy under load variation is noticeably better), the built-in PID loop, or the preset-speed PLC logic. For networked multi-axis applications with CANopen or EtherCAT, the C2000 series is the right platform — the B-series tops out at Modbus RTU.
Cabinet and clearance. IP20 / NEMA 1 means this drive belongs inside a control cabinet. It is not rated for direct exposure to dust, moisture, or operator contact. Leave at least 50 mm clear above and below for airflow. If multiple VFDs share a cabinet, mount them side by side rather than stacked — the heat rising from the lower drive raises the ambient temperature at the upper drive's intake.
Braking resistor sizing. The built-in braking transistor handles occasional deceleration of moderate-inertia loads. For frequent stops, high-inertia loads (large-diameter fans, flywheels, centrifuges), or rapid deceleration, wire an external braking resistor across the B1/B2 terminals. Without one, the drive trips on over-voltage (OV) as the motor regenerates energy back onto the DC bus during decel. Delta publishes recommended resistor values by model — for the 022B21A, start with 80–100 ohm, 150W minimum, and adjust based on your decel duty cycle.
EMC and cabling. The standard VFD022B21A does not include a built-in EMC filter. For installations in residential or mixed-use environments (IEC 61800-3 Category C1/C2), add an external RFI filter on the input side and use shielded motor cable with the shield terminated to ground at both the drive end and the motor frame. Keep control wiring (analog signals, Modbus) separated from power wiring by at least 150 mm inside the cabinet.
OEM Replacement & Cross-Reference
The VFD022B21A can replace several OEM-installed drives in light industrial and machine-tool equipment:
- Jet milling machines — Compatible with JTM949EVS-F08 and similar 2.2 kW three-phase spindle motor applications. Verify the motor nameplate FLA against the drive's 11 A rating before swapping. If the original drive used a different carrier frequency, adjust parameter P71 on the Delta to match the motor's acoustic and thermal characteristics.
- Generic 2.2 kW single-phase-input VFDs — Can replace Huanyang HY02D223B, Schneider ATV12HU22M2, and other 2.2 kW single-to-three-phase drives with comparable current ratings. Always go through the full motor parameter set (P01–P05) and run auto-tune (P05=1) rather than assuming default values from the old drive will carry over.
- Pump and fan VFD retrofits — If you are replacing an older PWM drive in a constant-pressure pump or HVAC fan application, wire the existing transducer to AVI/ACM, set the PID parameters (P125–P135), and the drive will run closed-loop without an external controller.
Sourcing
We stock the Delta VFD022B21A at our Shenzhen facility. 33 units available as of this listing.
Reference price: $463.00 — positioned well below the typical $600–860 range seen from Western distributors for this model. The difference comes from direct factory allocation and shorter logistics: Shenzhen to Southeast Asia and the Middle East moves in days, not weeks.
Submit an RFQ for a firm quote with confirmed lead time and shipping to your destination. We ship internationally with DDP and DAP terms available — specify your preferred Incoterms and destination port in the inquiry. Volume pricing available for orders of 10+ units.
Need a braking resistor, EMC filter, or spare keypad with your drive? Mention it in the RFQ — we can quote the complete bill of materials in a single shipment.