The FR-D740-080-NA is Mitsubishi Electric’s 1.5 kW three-phase 400 V input compact inverter from the FREQROL FR-D700 series — providing variable frequency drive capability for three-phase AC motors at 1.5 kW continuous rated output (4.0 A) from a three-phase 380–480 VAC power supply with V/F speed control, making it the cost-effective entry-level VFD solution for 1.5 kW three-phase 400 V motor applications in conveyor systems, fan drives, and pump control where basic variable speed is required without the advanced magnetic flux vector control and built-in Modbus RTU of the FR-E740 series. In stock at Atlantech Drives. Request your quote within 24-48 hours with worldwide shipping and 12-month warranty.
What Is the FR-D740-080-NA?
The FR-D740-080-NA is a FREQROL FR-D700 series variable frequency inverter providing 1.5 kW rated output from three-phase 380–480 VAC input — «D740» identifying the FR-D700 entry-level series with three-phase 380–480 V input, «080» the capacity code for 1.5 kW (4.0 A continuous rated output), and «NA» the North American UL/cUL-certified variant. The FR-D740-080-NA provides V/F (volts-per-hertz) speed control as the primary control mode — adequate for fans, pumps, and conveyors with quadratic or linear torque-speed characteristics where speed accuracy below 20 Hz is not critical. An optional simple magnetic flux vector control mode is available for improved low-speed torque at the cost of a motor auto-tuning setup step. At 1.5 kW from three-phase 400 V supply, the FR-D740-080-NA draws approximately 2.8 A per phase at full rated output — significantly lower per-phase current than the single-phase FR-D720-070-NA (7.0 A at 200 V single-phase) for equivalent motor output, reflecting the supply current balancing advantage of three-phase 400 V input at this power level. The built-in operation panel provides direct parameter access, frequency setting, and run/stop control without additional tools. Three programmable digital inputs, one analog speed reference input (0–5 VDC or potentiometer), and one relay output provide the basic control interface for standalone variable speed operation.
Key Technical Specifications
- Model: FR-D740-080-NA
- Rated Output Power: 1.5 kW
- Rated Output Current: 4.0 A (continuous)
- Input Power Supply: Three-phase 380–480 VAC, 50/60 Hz
- Output Voltage: Three-phase 380–480 VAC (variable frequency)
- Output Frequency Range: 0.2–400 Hz
- Control Method: V/F control (simple magnetic flux vector optional)
- Digital Inputs: 3 programmable inputs
- Analog Inputs: 1 speed reference (0–5V or potentiometer)
- Digital Output: 1 relay contact
- Communication: None built-in (optional RS-485 communication card)
- Certifications: UL, cUL (NA variant)
- Protection: IP20
- Operating Temperature: -10°C to 50°C (with derating above 40°C)
- Dimensions (W × H × D): 68 mm × 128 mm × 118 mm
- Weight: Approx. 1.0 kg
Series Comparison & Selection Guide
At 1.5 kW from three-phase 400 V supply, the FREQROL range offers three distinct product choices with different feature levels: the FR-D740-080-NA (basic V/F control, no built-in communication, lower cost), the FR-E740-080-NA (advanced magnetic flux vector control, built-in RS-485 Modbus RTU, 5 digital inputs, higher cost), and the FR-A840-00038-E2-60 (full-featured A800 series with regenerative braking, advanced motor control, network options, highest cost). The FR-D740-080-NA is the correct selection for applications where: the load is a fan or centrifugal pump with quadratic torque characteristic (low starting torque requirement), speed accuracy below 15 Hz is not critical (V/F control is adequate), PLC communication via Modbus RTU is not required, and the lower FR-D700 cost justifies the reduced features. For any application requiring Modbus RTU PLC integration, accurate speed regulation at low frequencies, or 5-input control flexibility, the FR-E740-080-NA is the appropriate upgrade. The FR-D740-080-NA versus the FR-D720-070-NA comparison: both provide 1.5 kW motor output, but the FR-D740-080-NA requires three-phase 380–480 VAC (appropriate for European and international three-phase supply), while the FR-D720-070-NA uses single-phase 200–240 VAC input. In facilities with established three-phase 400 V panel infrastructure, the FR-D740-080-NA’s three-phase input provides balanced supply loading and lower input current per phase.
Troubleshooting Guide
For FR-D740-080-NA inverters displaying E.OC1 (overcurrent during acceleration) at startup with a correctly sized motor, verify that the acceleration time (parameter Pr.7, Acceleration time) is not set too short for the connected load inertia — a very short acceleration time demands high motor current during rapid speed ramp-up, triggering the overcurrent protection before the motor reaches the set frequency. Increase the acceleration time in 1-second increments until E.OC1 clears during normal load acceleration. If E.OC1 persists even with extended acceleration time, verify the motor’s rated current against the FR-D740-080-NA’s 4.0 A rated output — a motor with rated current above 4.0 A is undersized for the inverter and will consistently trigger overcurrent on acceleration. For FR-D740-080-NA inverters displaying E.OV1 (overvoltage during deceleration) with a high-inertia load, the deceleration time (parameter Pr.8) is too short — the high-inertia load generates regenerative energy during rapid deceleration that raises the DC bus voltage above the overvoltage trip threshold. Increase the deceleration time until E.OV1 clears, or install an external braking resistor on the P and PR terminals for faster deceleration capability without overvoltage. For FR-D740-080-NA units that operate correctly in cool ambient temperatures but generate E.OHT (overtemperature) alarms during peak summer ambient temperatures, verify the installation provides the minimum clearances (50 mm above and below the inverter heatsink) and that the panel is not sealed without ventilation — the FR-D740-080-NA at 1.5 kW relies on natural convection cooling and requires adequate panel airflow to maintain heatsink temperature within specification at elevated ambient temperatures.
Frequently Asked Questions
Q: Can the FR-D740-080-NA control a standard IEC 1.5 kW 4-pole motor at 50 Hz rated speed from a 60 Hz North American supply?
A: Yes. The FR-D740-080-NA’s output frequency is independently programmable from 0.2 to 400 Hz regardless of the input supply frequency — configure the base frequency (parameter Pr.3) to 50 Hz for a 50 Hz-rated motor even when the input supply is 60 Hz. The inverter rectifies the 60 Hz input to DC and generates the output frequency independently, so a 50 Hz IEC motor operates at its rated speed and voltage when the FR-D740-080-NA output is set to 50 Hz, without the over-excitation that would occur if the motor were connected directly to a 60 Hz supply.
Q: Is the FR-D740-080-NA suitable for controlling a 1.5 kW motor driving a positive displacement pump (constant torque load) as well as a centrifugal pump (variable torque)?
A: The FR-D740-080-NA’s V/F control is adequate for both load types at moderate speed ranges. For centrifugal pumps (variable torque, low starting torque requirement), V/F control is optimal and efficient. For positive displacement pumps (constant torque, requires full torque at all speeds including low speed), V/F control may produce insufficient torque at speeds below 20 Hz, potentially stalling the motor under full load at low speed. For positive displacement pump applications requiring reliable low-speed operation under load, the FR-E740-080-NA with advanced magnetic flux vector control is the safer specification — the flux vector control provides rated torque at 3 Hz or lower, well below V/F control’s practical low-speed torque limit.
Q: What optional communication card is available to add RS-485 Modbus RTU to the FR-D740-080-NA?
A: The FR-D700 series supports the FR-A7NC (RS-485 communication option) or equivalent optional communication card installed in the option connector slot on the FR-D740-080-NA — this adds RS-485 Modbus RTU capability equivalent to the built-in RS-485 of the FR-E700 series. The total cost of FR-D740-080-NA plus FR-A7NC communication card typically approaches or exceeds the cost of the FR-E740-080-NA, which includes RS-485 Modbus RTU as standard — evaluate the full cost comparison before specifying the FR-D740 plus communication card versus specifying the FR-E740 directly.
Do you need more references from this brand? Explore our full catalog of Mitsubishi here: https://atlantechdrives.com/manufacturers/mitsubishi/
