Description
Directing high-capacity three-phase motor applications, the Mitsubishi Electric FR-A840-30K-1 variable frequency drive provides precise velocity and torque regulation for industrial drivetrains. Built on the high-performance FR-A800 architecture, this inverter is designed to drive standard induction motors and permanent magnet synchronous motors alike. The configuration includes an FM pulse train terminal for accurate physical feedback loops, integrated RS-485/422/232 serial communications, and standard compliance ratings for global heavy-industry deployments.
Features
- Real sensorless vector control and advanced vector control for precise torque limitation at zero speed.
- FM control terminal configuration delivering high-resolution pulse train tracking outputs.
- Built-in Modbus-RTU and standard serial protocols for direct automation system integration.
- Long-life cooling fans and capacitors with automated diagnostic maintenance warnings.
- High-speed response capabilities to absorb sudden mechanical load changes.
Applications
- Industrial fan, blower, and high-volume ventilation systems.
- Heavy-duty conveyancing, material handling, and material transfer networks.
- Centrifugal pumps, positive displacement pumps, and process control fluids piping.
- Extruder drives, mixers, and industrial processing machinery.
Technical Specifications Table
| Manufacturer |
Mitsubishi Electric |
| Model Number |
FR-A840-30K-1 |
| Series |
FR-A800 |
| Applicable Motor Capacity |
30 kW |
| Input Voltage Class |
Three-phase 400 V Class |
| Rated Input Power Supply |
Three-phase 380 to 500 V AC, 50 Hz / 60 Hz |
| Rated Output Current |
57 A |
| Output Capacity |
43 kVA |
| External Communications |
RS-232, RS-422, RS-485 |
| Control Terminal Layout |
FM Term (Pulse Train Output) |
| Safety/Compliance Standards |
CE, UL, cUL, RoHS (Grade 6) |
| Dimensions (W x H x D) |
325 mm x 550 mm x 195 mm |
| Shipping Weight |
24 kg |
Empirical Engineering Insights
Alternative Models & Compatibility: The FR-A840-30K-1 directly replaces older FR-A740-30K models but features a modified terminal orientation. When migrating from the A740 series, control terminal locations should be verified against updated layouts. Note that the '-1' suffix indicates an FM terminal configuration (pulse train monitoring) instead of the AM terminal (analog voltage monitoring) found on other regional variations.
Application Pitfalls & Engineering Notes: Operating at its nominal 57 A output in high-ambient environments can degrade internal components. If housing the VFD in a sealed IP54 control cabinet, external heat exchangers must be sized to dissipate thermal loads generated by the drive’s full-capacity operation. If the motor is operated continuously at low speeds and high torque, external force-cooling on the motor must be implemented to prevent thermal faults.
Commissioning & Wiring Tips: Ensure parameters such as Pr. 291 (Pulse train output selection) are properly assigned to route motor speed, current, or voltage telemetry output to your external controller. Ground loop prevention is critical when wiring the FM terminal to high-speed counters: use double-shielded twisted-pair cables with the shield grounded only on the inverter frame.
Installation Guidelines
CRITICAL WARNING: HIGH-VOLTAGE HAZARD
De-energize all primary incoming power sources before opening the cover. Wait at least 10 minutes to allow the internal DC bus capacitors to fully discharge. Verify that the DC voltage across terminals P/+ and N/- is below 20 VDC using a certified multimeter prior to commencing physical wiring or service work.
1
Mount the inverter vertically to a rigid, flat, heat-resistant panel. Ensure a minimum vertical clearance of 100 mm above and below the cooling ducts to maintain unrestricted airflow.
2
Wire the three-phase AC input supply line to terminals R/L1, S/L2, and T/L3. Never connect mains power to the output terminals.
3
Route shielded motor cabling to output terminals U, V, and W. Bond the shield ground securely to the frame ground clamp on the drive.
4
Connect control signals to the control terminal block, routing digital cables separately from the power and motor cables to prevent electromagnetic interference.