The three-stage VARIO-SP® diaphragm pumps, with its variable speed drive system, attains significantly higher pumping speed and a better ultimate vacuum than the corresponding fixed speed pump. The brushless motor (maintenance-free) enables easy integration of the pump into other equipment, and operation independent of line voltage. The motor speed is either fixed or can be adjusted externally via electronic control signals for adaptation to process requirements.

• Contamination-free pumping and evacuation
• High flow rate even near ultimate vacuum
• Fast pump down at high motor speed, maintain vacuum with reduced motor speed
• Extremely compact and mountable in any position
• Pump is silent and vibration-free, with an extended lifetime for its diaphragms

For the model MD 1C VARIO-SP®, the chemical resistance of the pump's internal flowpath is available as a chemistry design version with gas ballast valve and superior vapor tolerance. All major parts of the chemistry design pump in contact with pumped media are made of chemically resistant fluoroplastics.