Manufacturer: Mitsubishi Electric
Product No.: FR-A840-3.7K
Country of origin:United States
Product Type: Variable Frequency Drives
Payment: T/T, Western Union
Weight: 4400g
Shipping port: Xiamen
Warranty: 12 months
Engineered for high-torque heavy industrial loads, the Mitsubishi Electric FR-A840-3.7K variable frequency drive provides precise vector speed control within the FREQROL-A 800 series portfolio. This high-performance inverter accommodates four distinct duty ratings (SLD, LD, ND, and HD), allowing system integrators to scale motor driving capacity from 2.2 kW up to 5.5 kW based on load profiles. Operating on a three-phase 380 to 500 VAC supply, the FR-A840-3.7K features advanced sensorless vector control, PM sensorless vector control, and built-in RS-485 communications to deliver exceptional speed stability, low-speed torque performance, and seamless automation system integration.
| Parameter | Value / Specification |
|---|---|
| Manufacturer | Mitsubishi Electric |
| Model Number | FR-A840-3.7K |
| Series | FREQROL-A 800 |
| Input Voltage / Frequency | 3-phase 380 to 500 VAC, 50 Hz / 60 Hz |
| Allowable Voltage Fluctuation | 323 to 550 VAC, 50 Hz / 60 Hz |
| Normal Duty (ND) Capacity | 3.7 kW (Rated Current: 9.0 A) |
| Super Light Duty (SLD) Capacity | 5.5 kW (Rated Current: 12.6 A) |
| Heavy Duty (HD) Capacity | 2.2 kW (Rated Current: 6.0 A) |
| Output Voltage Range | 3-phase 380 to 500 VAC |
| Output Frequency Range | 0.2 to 590 Hz (Vector/Sensorless limit: 400 Hz) |
| Overload Current Rating (ND) | 150% for 60 seconds, 200% for 3 seconds (at 50 degC) |
| Cooling Method | Forced Air Cooling |
| Enclosure Protection Rating | IP20 (Closed type) |
| Operating Temperature | -10 to +50 degC (LD/ND/HD without freezing); -10 to +40 degC (SLD) |
| Storage Temperature | -20 to +65 degC |
| Net Mass | 3.3 kg (7.28 lbs) |
| Shipping Weight | 4.4 kg (9.70 lbs) |
| Terminal Designation | Signal Type / Assignment | Electrical Specification |
|---|---|---|
| R/L1, S/L2, T/L3 | AC Power Input | 3-phase 380 to 500 VAC, 50/60 Hz |
| U, V, W | Motor Output Connections | 3-phase modulated variable AC |
| Terminal 2 | Analog Voltage Frequency Command Input | 0 to 5 VDC, 0 to 10 VDC (Selectable) |
| Terminal 4 | Analog Current Frequency Command Input | 4 to 20 mA (or 0 to 20 mA) |
| Terminal 1 | Auxiliary Analog Input (Frequency Offset) | -10 to +10 VDC or -5 to +5 VDC |
| 12 Control Terminals | Configurable Contact Inputs (Multi-speed, Reset, STO) | 24 VDC opto-isolated logic |
The FR-A840-3.7K serves as a direct technical successor to legacy FR-A740-3.7K models. It maintains matching physical mounting patterns, but boasts improved vector algorithm execution. When upgrading a system, parameters from older drives can be extracted and loaded into the newer inverter using Mitsubishi FR Configurator2 software via the integrated USB host port, though phase monitoring characteristics should be verified to prevent minor tuning anomalies on high-inertia loads.
Engineers must exercise caution when operating in the Super Light Duty (SLD) rating class. While SLD elevates continuous output current capacity to 12.6 A for variable torque loads (pumps and fans), the permissible operating ambient temperature drops to 40 degC maximum (compared to 50 degC for standard ND and HD configurations). Placing an SLD-configured unit inside an unventilated outdoor panel can lead to rapid thermal de-rating faults (E.THT or E.TBM) if cabinet ambient temperatures surpass 40 degC.
Ensure that the hardware slide switches located on the control circuit terminal block are configured to match the intended signal type before applying control voltage. If configuring Terminal 4 for 4 to 20 mA current input, check that Parameter 267 is set to '0' (initial value) and the input selection switch is in the 'I' position. Leaving the switch in 'V' (voltage) while applying a current loop input can damage the analog input circuitry.
CRITICAL WARNING: HIGH VOLTAGE RISK
Before executing any wiring or maintenance operations on this variable frequency drive, isolate the AC primary supply and wait a minimum of 10 minutes. Use a calibrated DC voltmeter to confirm that the DC bus charge LED has extinguished and that voltage across terminal P/+ and N/- has dropped below 30 VDC. Failure to observe discharge times can result in lethal shock or device destruction.
Global Express Shipping
Returns & Warranty
Global Express Shipping
Returns & Warranty
Orders are processed and delivered Monday-Friday (excluding public holidays).
For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Country of origin |
United States
|
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