Peristaltic pumps

The motor’s control for the application in a peristaltic pump may seem very simple: it is, in fact, a free running rotation of the motor.

There is, however, a criticality linked to the operation of a peristaltic pump: the load is not constant but has torque peaks, which is the reason why the motor rotation speed must be as stable as possible to maintain constant pressure and constant dosage.

Typically, this control is carried out by 3 types of motor:

1) Brushed DC motors
2) Brushless DC motors with gearbox
3) Stepper motors

Let's see what are the advantages and disadvantages of this 3 solutions:

Control with direct current motors is the most economical solution, especially due to the simplicity of the control electronics.
However, this solution has big limits related to reliability -given by the duration of the motor- and to the control resolution in speed.

The control with DC bruhless motor with gearbox is surely a more performing control mode than DC motors one: the high efficiency of brushless motors can, in fact, ensure important power performance.
The limit is represented, in this case, by the gearbox, a component with a significant cost and a limited life due to mechanical complexity.

Stepper motors provide high torque at low speeds and allow installation on a peristaltic pump in direct-drive (without gearbox).
The performance stepper motors can achieve are similar to a brushless motor control but with greater reliability, greater compactness and lower costs given by the absence of the gearbox.

The limit of this control is the maximum power of the solution. The stepper motors, in fact, have a decreasing torque as the speed increases: this limits the maximum speed and, therefore, the power applicable to the pump.

Ever Elettronica has designed and produced "ad hoc" motion control solutions for peristaltic pumps, by using stepper and brushless technology.

Specifically we propose:

• brushless DC motors with programmable integrated drives, for stand alone applications control
• brushless DC motors and programmable drive for brushless DC motors up to 400 W
• vector programmable drive with Nema 23 or Nema 24 stepper motor integrated
• vector programmable drive, 3,4 Nm stepper motor and incremental encoder or absolute encoder
• vector programmable drive for 2-phase stepper motor

Stepper motor, first of all: why?

We think that the movement control of a peristaltic pump with stepper motors is particularly optimal for two reasons:

• closed loop of torque, whereby by modulating the current according to load, we manage to keep the average current value as low as possible, thus keeping under control motor’s temperature increase
• the programmability of our stepper drives: our easy and intuitive e3PLC programming environment allows you to set the desired parameters without the knowledge of any particular programming languages.

Click on the links above for further details!