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Applied Motion Products, founded in 1978, specializes in high-precision, cost-effective motion control products. We offer a full complement of stepper and servo, drives, motors, controllers, gearheads, and power supplies to serve a diverse industrial and OEM customer base.

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Integrated Closed-Loop Step Motors from Applied Motion Products Solve Heat Problems in Peristaltic Pumps Used with Bioreactor System

POSTED 02/18/2020

Watsonville, CA - Applied Motion Products solved heat problems associated with a peristaltic pump system that supplies materials to a bioreactor by replacing open-loop step motors with closed-loop step motors.  A peristaltic pump, with internal tubing that separates media from pump components, offers a sanitary method to supply the bioreactor with various fluids to grow cell cultures in the development of new medicines. Step motors are used to drive the pump head, compressing and releasing the pump tubing to move media into the bioreactor chamber.

Peristaltic pump system for a bioreactor
Initially, excessive heat generated by open-loop step motors elevated the temperature of fluids being pumped into the bioreactor.  The higher temperatures, in turn, adversely affected biological processing times and reduced yields.  Integrated closed-loop step motors from Applied Motion Products eliminated the heat problem by operating cooler and consuming less power than open-loop step motors.
Incorporating encoder feedback and servo-control firmware, the closed-loop step motor system’s current is controlled to precisely meet torque demands. Drawing only enough current as needed, the closed-loop step motor generates substantially less heat than an open-loop step motor.  Closed-loop step motors also run quieter and more smoothly than their open-loop counterparts.  Open-loop step motors operate continuously at full current regardless of load requirements, which results in excessive heat generation.

Switching to a closed-loop step motor also enabled the life sciences company to use a single-size NEMA 23 step motor to address all combinations of pump tubing and media instead of stocking different pump and motor sizes.  This change to a single motor supported the development of one standard pump head assembly that required only switching tube adapters to dispense different materials to the bioreactor.

Using an integrated motor design also reduced componentry and decreased space requirements in the control panel.  Combining a step motor, encoder, drive, controller and connectors into a single package, the integrated motor eliminated the need for cabling to connect separate motion control components together, which freed space in the very small control panels.  Dual-port Ethernet connections enabled daisy-chain connections of Ethernet signals among multiple motors to reduce network cables routed around the equipment and back to the control panel (see photo 2).

StepSERVO™ Integrated Motors from Applied Motion Products

About Applied Motion Products       
Applied Motion Products specializes in high-precision, cost-effective motion control products including stepper and servo motors, drives, controllers, gearheads, and power supplies.  The company serves a diverse industrial and OEM customer base with both standard and customized products.  With in-depth motor and control expertise, Applied Motion Products works with customers from initial concept and design through finished product and production to provide the best motion control solutions to a range of markets.