Velmex NF90-2 Programmable Stepping Motor Controller 3-Axis RS-232 120V AC

Velmex NF90-2 Programmable Stepping Motor Controller 3-Axis RS-232 120V AC

The Velmex NF90-2 is a programmable stepping motor controller designed to drive up to three stepper motors, one at a time, under microprocessor-based control. It incorporates a single-chip microprocessor with on-chip RAM for temporary storage of user programs and motion parameters. Commands and motion data are entered via an RS-232-C interface from a host computer, terminal, or programmable controller, and the unit can operate in either interactive (host-driven) or stand-alone (stored-program) mode. Wired and factory-matched for direct connection to Velmex UniSlide motors and assemblies.

Specifications & What's Included

• Model: NF90-2
• Manufacturer: Velmex, Inc. — East Bloomfield, NY (Made in USA)
• Number of motors controlled: Up to 3 (sequentially, one at a time)
• Interface: RS-232-C
• Input voltage: 95–130 VAC, 50/60 Hz (120V standard); 190–260 VAC available with European fuses
• Power consumption: 100W
• Fuse: 7 Amp Fast Blow (inline fuse holder)
• Step resolution: 400 steps/revolution (0.9° step angle)
• Output current: 0.7 to 4.7 A/phase (factory matched to specific motor)
• Slew speed: Up to 1,000 or 2,000 steps/sec (switch settable)
• Acceleration/Deceleration: 2,000 to 100,000 steps/sec² in 2,000 steps/sec² increments
• Operating modes: Interactive (host-driven) and stand-alone (user program stored in RAM)
• JOG/slew mode: Single-step jog or continuous slew
• Enclosure: All-metal; linear-type motor and logic power supplies for low RFI/EMI
• Motor impedance: 7 Ohms (per rating plate)
• Compatible with: Velmex UniSlide motors and linear slide assemblies
• Includes: Two motor cables (with Molex-style connectors) and AC power cord

Applications

The Velmex NF90 series was designed for laboratory automation, precision positioning, and motion control applications where multiple linear or rotary stepper-motor-driven axes need to be sequenced under computer or stand-alone program control. It is commonly paired with Velmex UniSlide linear translation stages in optical, microscopy, metrology, and scientific instrumentation setups — anywhere repeatable, programmable positioning is needed. The RS-232-C interface makes it straightforward to integrate with a wide range of host computers or PLCs, and the stand-alone mode allows it to execute stored motion sequences without a continuously connected host. Velmex NF90-series controllers date from the 1980s–1990s era of RS-232-based laboratory automation and remain in active use in legacy Velmex stage installations and in research labs that maintain established motion-control setups.