The 3.7 kW line of the VFD-M family
The VFD037M23A sits in Delta's VFD-M series of general-purpose sensorless vector control micro drives, aimed at the 3.7 kW / 5 HP motor class on a 3-phase 200-240 VAC supply. Rated 17 A continuous output at 6.5 kVA, it covers pumps, conveyors, fans, and small compressors in that power band without oversizing the cabinet footprint.
Input envelope and what it tolerates on plant power
Three-phase 200-240 VAC at 50/60 Hz is the rated input, with ±10% voltage tolerance (180-264 VAC) and ±5% frequency tolerance (47-63 Hz) — enough headroom to ride through the brown-outs and small generator excursions seen on factory feeders. Rated input current is 19.6 A, which sets the upstream breaker and wire sizing, not the motor nameplate.
Output side: from low-end torque to 400 Hz
Output frequency spans 0.1-400 Hz with a carrier window of 1-15 kHz; maximum output voltage tracks the input rail proportionally. At the default carrier the motor runs quiet; pushing toward 15 kHz cleans up acoustic noise but trims continuous output current, a tradeoff that matters on constant-torque loads like conveyors run near rated rpm. Sensorless vector control is the headline control mode — usable down to low Hz without encoder feedback, which is the practical reason the VFD-M is specified where low-speed holding torque matters but an encoder retrofit is not in the budget.