BaldorVS1ST11-01 HP / 0.75 kW AC Microdrive, 115 V Single-Phase In, 230 V Three-Phase Out, 4.3 A, IP20

Product Description

What this part is

A Baldor VS1ST11-0 — a 1 HP / 0.75 kW AC microdrive from the VS1 Microdrive range, sold by Baldor as a “starter replacer”: a compact adjustable-frequency drive intended to go in where a fixed-speed contactor starter was, and run out of the box with minimal setup. It is a V/Hz (volts-per-hertz) PWM inverter for standard three-phase induction motors.

Decoding the order code

VS1 — Baldor VS1 general-purpose inverter familyST — Starter Replacer microdrive variant1 (first digit) — input voltage code: 115 V AC single phase1 (second digit) — horsepower: 1 HP-0 — option code: none fitted (a T suffix on other models denotes fitted keypad/other options)

Correcting the source data

Earlier copy quoted 16 A. That figure is the input current drawn from the 115 V single-phase supply, not the motor output. Rated output current is 4.3 A, and that is the number to size the motor against. The drive is also single-phase in, three-phase out — it is not a single-phase output drive and will not run a single-phase motor.

Published specifications

Type: AC variable frequency microdrive, PWMMotor rating: 1 HP / 0.75 kWInput: 115 V AC, single phase, 50/60 HzOutput: 230 V AC class, three phase, 4.3 A ratedControl method: V/Hz (volts per hertz) open loop — not sensorless vector, not closed-loop flux vectorEnclosure: IP20, open panel-mountOption codes fitted: noneUPC: 781568454404Origin: United Kingdom (nameplate)

What these specs mean in practice

The single-phase 115 V input is the reason to buy this drive: it lets a three-phase 230 V motor run from an ordinary single-phase supply, which is why these turn up on small machine tools, pumps and conveyors in shops with no three-phase service. The trade-off is control performance. V/Hz gives smooth speed adjustment but not the low-speed torque or speed holding of a vector drive, so it is not the right choice for a hoist, a winder or a spindle needing constant torque near zero speed. Size against the motor’s full-load amps against the 4.3 A rating, not against the horsepower label.

Braking: what you still need:
Any braking resistor is external and is not supplied. For an overhauling or high-inertia load, size and fit a resistor per the VS1ST manual (MN767), or extend the deceleration ramp until the drive stops reporting a bus overvoltage.

Installation and setup notes

IP20 means open-board protection: the drive belongs inside an enclosure, away from coolant, swarf and washdown. Set the motor nameplate data, base frequency and current limit before running. Keep the motor cable short and screened where possible — a 115 V input drive with a long output run will nuisance-trip.

What is not included

Drive unit only. No braking resistor, no input or output reactor, no EMC/RFI filter, no remote keypad or operator panel, no communication option module, no potentiometer or speed pot kit, no enclosure, no motor cable, no terminal or connector kits and no printed manual.

Quantity and configuration

Sold as one drive unit.

Interchange guidance

VS1ST11-0, VS1ST110 and VS1ST11 0 are the same drive. Within the range the voltage digit is decisive: VS1ST21-0 and VS1ST81-0 are 230 V input models and are not substitutes for a 115 V feed, while VS1ST11P5-0T is 1.5 HP with options fitted. VS1STS is the extreme-duty variant (manual MN767S) with a different enclosure. Baldor drives of this era are now supported under ABB; the VS1 range is discontinued.