33VM62-028-4 Pacific Scientific
Wake Industrial LLC is not an authorized distributor of this product.
No Tariffs On US Orders- Straightforward Pricing: No Rush Fees, No Credit Card Fees
The Pacific Scientific 33VM62-028-4 is a PMDC servomotor from the Low Inertia PMDC Servomotors series with a basket-wound hollow rotor and Alnico V-7 magnet material. It uses carbon brushes for commutation and features both analog tachometer and optical encoder feedback. The motor has no forced-air cooling and each encoder uses dual channels with a zero index and square wave signal.
To contact sales for pricing and lead time:
Payment Methods
Shipping Methods
Our Credentials
Product Description:
The 33VM62-028-4 direct-current servomotor is built by Pacific Scientific and supplied under the Low Inertia PMDC Servomotors series. As a permanent-magnet DC unit, it converts drive current from a matched amplifier into controlled shaft torque and speed for indexing tables, material handlers, and other motion axes in industrial automation. Its compact frame and low rotor inertia support tight velocity loops and rapid reversals. These characteristics allow the motor to perform quick point-to-point movements in machinery that requires responsive motion control.
Commutation is handled by carbon brushes, which mechanically switch the armature current without requiring additional sensors. The motor uses no forced-air cooling, so natural convection through the frame removes heat during operation. Its feedback package combines a standard analog tachometer with an optical encoder. The tachometer supplies a direct velocity signal, while the encoder provides a dual-channel quadrature output for position and direction monitoring. Flutter remains below <1.0% p-p, helping limit speed ripple during regulated operation. The interface electronics require 5 VDC ±5% at 150 mA. This feedback arrangement is compatible with PMDC servo drives that accept a direct analog tachometer signal for velocity-loop control.
The optical stage uses an LED emitter, and its modulated beam generates a square-wave output compatible with TTL or line-driver receivers. A dedicated zero-index pulse marks each mechanical revolution, supporting repeatable homing without an external reference sensor. The internal code wheel has low mass, keeping encoder inertia below 0.00001 oz-in-s² and limiting its effect on servo response. The magnetic circuit contains Alnico V-7 permanent magnets, which provide stable magnetic flux across a broad temperature range. Torque is produced by a basket-wound hollow rotor that reduces rotational mass and supports rapid acceleration. The optical feedback signals allow the connected drive to monitor incremental movement while the analog tachometer supplies continuous velocity information. The combination of low encoder inertia and a lightweight rotor supports high-bandwidth control without adding a forced-air cooling system.
