820 4KW General-purpose Inverter
Overview NH820 4KW general-purpose VFD is a mid-size vector variable frequency drive for standard three-phase 380V asynchronous motors, bridging low-power small drives and medium-power heavy-duty inverters. Adopts high-speed dedicated DSP chip, optimized torque compensation algorithm to guarantee stable output under medium fluctuating load. Balanced size and performance, compatible with constant torque and…
Overview
NH820 4KW general-purpose VFD is a mid-size vector variable frequency drive for standard three-phase 380V asynchronous motors, bridging low-power small drives and medium-power heavy-duty inverters. Adopts high-speed dedicated DSP chip, optimized torque compensation algorithm to guarantee stable output under medium fluctuating load.
Balanced size and performance, compatible with constant torque and variable torque equipment. Equipped with 10 main frequency sources + 10 auxiliary frequency fine-tuning sources, flexible for complex process control. Complete stall & fast current limiting protection to reduce unexpected shutdowns for continuous production lines.
Application Industries
- Medium power standard cabinet size, plastic shell, easy replacement for old 4KW inverters
- Enhanced slip & torque compensation, stable torque output under fluctuating medium load
- Four V/F curve modes: linear, multi-point, full/partial V/F separation for different loads
- Fast current limiting & stall control, avoid frequent over-current tripping during frequent start-stop
- Built-in independent PID closed loop, realize automatic pressure/flow constant control for pump/fan
- 4 groups independent acceleration/deceleration time 0.1~6500s, S-curve soft start for conveyor & wire drawing
- Auto carrier frequency adjustment, reduce motor noise at low speed
| Item | Parameter |
|---|---|
| Rated Power | 4KW, 3 Phase 380V Input (-15%~+15%) |
| Output Frequency | 0–500Hz, resolution 0.01Hz |
| Carrier Frequency | 0.8kHz~12kHz auto-adjust |
| Control Mode | V/F Vector Control |
| Starting Torque | G-type 0.5Hz/150% high starting torque |
| Overload Capacity | G-type 150% rated current sustain 60s |
| Speed Range & Precision | 1:100 speed ratio, ±1% steady speed accuracy |
| I/O Interface | 6 digital input (high-speed pulse); dual analog input 0~10V/0~20mA; high-speed pulse output 0~50kHz, relay & dual analog output |
| Built-in Functions | 16-speed PLC, jog control, DC braking (0~100% braking current), wobble frequency, speed tracking |
| Communication | RS485 Modbus compatible, multi-channel frequency source superposition |
| Protection | Full set of over-current, over/under voltage, overheat, phase loss, short-circuit protection |
Installation dimensions of the keyboard base

Diagrams of the overall dimensions and installation dimensions of the plastic structure

| Applicable models | Rated output power (kW) | Input voltage | A (mm) | B (mm) | H (mm) | W (mm) | D (mm) | Installation aperture (mm) |
|---|---|---|---|---|---|---|---|---|
| 820/860S | 0.4~2.2 | Single‑phase 220V range: -15%~ +15% |
90 | 157 | 170 | 101 | 142 | Φ5 |
| 820/860S/860E | 0.75~2.2 | Three‑phase 380V range: -15%~ +15% |
90 | 157 | 170 | 101 | 142 | Φ5 |
| 820/860S/860E | 4~5.5 | 111 | 183 | 197 | 129 | 175 | Φ5 | |
| 820/860S/860E | 7.5 | 137 | 237 | 256 | 157 | 190 | Φ5 | |
| 820 | 11 | 137 | 237 | 256 | 157 | 190 | Φ5 | |
| 820 | 15~22 | 151 | 303 | 320 | 170 | 222 | Φ5.8 | |
| 820 | 30~37 | 205 | 366 | 380 | 218 | 235 | Φ6 |
Diagrams of the overall dimensions and installation dimensions of the sheet metal structure

| Applicable models | Rated output power (kW) | Input voltage | A (mm) | B (mm) | H (mm) | W (mm) | D (mm) | Installation aperture (mm) |
|---|---|---|---|---|---|---|---|---|
| 820/860S | 0.4~2.2 | Single‑phase 220V range: -15%~ +15% |
90 | 157 | 170 | 101 | 142 | Φ5 |
| 820/860S/860E | 0.75~2.2 | Three‑phase 380V range: -15%~ +15% |
90 | 157 | 170 | 101 | 142 | Φ5 |
| 820/860S/860E | 4~5.5 | 111 | 183 | 197 | 129 | 175 | Φ5 | |
| 820/860S/860E | 7.5 | 137 | 237 | 256 | 157 | 190 | Φ5 | |
| 820 | 11 | 137 | 237 | 256 | 157 | 190 | Φ5 | |
| 820 | 15~22 | 151 | 303 | 320 | 170 | 222 | Φ5.8 | |
| 820 | 30~37 | 205 | 366 | 380 | 218 | 235 | Φ6 |

| Applicable models | Machine type (kW) |
Overall dimensions | Installation dimensions | Installation hole diameter | |||
|---|---|---|---|---|---|---|---|
| H(mm) | W(mm) | D(mm) | H1(mm) | W1(mm) | mm | ||
| 820/860S/860E | 11‑15 | 340 | 204 | 214 | 325 | 150 | Φ6 |
| 820/860S/860E | 18.5‑22 | 360 | 224 | 214 | 345 | 150 | Φ6 |
| 820/860S/860E | 30‑37 | 380 | 262 | 220 | 360 | 192 | Φ9 |
| 820 | 45 new | 480 | 270 | 250 | 465 | 190 | Φ7 |
| 820 | 45‑75 | 450 | 330 | 259 | 430 | 240 | Φ9 |
| 860S/860E | 45‑75 | 570 | 380 | 263 | 547.5 | 240 | Φ10 |
| 860S/860E | 90‑132 | 610 | 400 | 286 | 587.5 | 240 | Φ12 |
| 860S/860E | 160‑220 | 760 | 500 | 355 | 735 | 200 | Φ12 |
| 860S/860E | 250‑400 | 862 | 750 | 455 | 832 | 250 | Φ12 |
| 820/860S | 450‑560 | 1122 | 950 | 505 | 1092 | 350 | Φ12 |
| 820/860S | 630‑750 | 1045 | 1050 | 505 | 1015 | 400 | Φ12 |















