Electricity and Control July 2024

CONTROL SYSTEMS + AUTOMATION : PRODUCTS + SERVICES

Improved dosing of aggressive chemicals

New products available from Mouser Electronics and through TRX Electronics in South Africa include TE Connectivity’s Vertical USB 3.2 A Gen 1 THT Receptacle Connectors and Harwin’s Flecto Floating Connectors. The Flecto Floating Connectors are ideal for high performance applications with multiple micro-pitch interconnects. They are designed to provide movement in the X, Y, and Z axes of the male connector, and the movement allows for added location tolerance. Flecto connectors feature low-stress mating connections with mated heights up to 29.9 mm nominal, and the mating area of the male connector can move by up to ±0.8 mm from the centreline. This design compensates for positional misalignment across multiple connectors, eases stresses from misalignment, and helps maintain the contact force over time. Harwin Flecto Floating Connectors are suitable for factory automation applications. They can be used, for example, for drives and controls, robotics, sensor units Gentle and low-pulsation dosing of aggressive chemicals without pressure peaks and with minimised dead time. This is made possible by MEMDOS SMART, a new stepper motor-driven dosing pump from Lutz-Jesco. The Industry 4.0-compatible dosing pump can be operated as easily and reliably as a smartphone via its full-colour touch display. Wastewater treatment plants, power stations and car washes all need to dose aggressive chemicals on a daily basis: wastewater treatment plants have to dose floc culants into the water, power stations have to dose rust inhibitors to their piping, and car washes need to dose detergents to their cleaning brushes. These substances are often introduced via dosing pumps equipped with a diaphragm in the dosing head. The backwards move ment of the diaphragm generates negative pressure in the pump head, which draws liquid in. When it moves forwards, the fluid is expelled from the pump head. It is a simple and reliable principle with just one down side: conventional models on the market usually work with standard motors running at a constant speed that maintain equal diaphragm stroke times during priming and ejection. This is disadvantageous because fluid de livery stops during the vacuum generation phase. The constant interruptions reduce efficiency and they lead to a phenomenon known as ‘pulsation’. This can cause pressure fluctuations in the lines that impair the accuracy of the dosing and, in the worst case, result in damage and outages. “Pump operators often have to buy expensive accessories such as pulsation dampers to manage this detrimental effect,” says Steffen Roth, Head of Development at Lutz-Jesco GmbH. “Our new generation Floating connectors for factory automation

of dosing pumps – MEMDOS SMART – provides an economical alternative.” Core to the new dia phragm dosing pumps is a drive with a microprocessor diaphragm

controlled stepper motor. Unlike standard motors, the stepper motor can be run asynchronously. This means the dosing pump can operate at different speeds for the suction stroke and pressure stroke. It enables operation of the motor at a higher speed during suction, thereby creating negative pressure which draws in the fluid more quickly. The vacuum phase, a dead time with standard motors, is reduced to a minimum. After priming, the stepper motor then operates at a slower speed to expel the fluid in a controlled and even way, without an abrupt increase in pressure. A slow mode is available for highly viscous media. “The stepper motor enables an almost constant sup ply stream, which permits the gentle, low-pulsation dos ing of aggressive chemicals without pressure peaks and with minimised dead time,” Roth emphasises. The repet itive accuracy of the MEMDOS SMART series diaphragm pumps is +- one per cent across the entire dosing range. “The stepper motor-driven diaphragm dosing pumps meet the need for high-precision reproducible industrial dosing applications.” The MEMDOS SMART is available in eight perfor mance levels, with delivery rates ranging from two litres per hour at a pressure of 20 bar up to 180 litres per hour at four bar. There are four different versions to cover all market requirements. □

Core to the new diaphragm dosing pumps is a drive with a microprocessor controlled stepper motor.

and vision systems. They are also suitable for various applica tions in electric vehi cles, LED displays, and security cameras. authorised independ ent representative for Mouser Electronics

TRX Electronics is the

Harwin Flecto Floating Connectors are suitable for use in factory automation and other applications.

Inc. in South Africa. Mouser is one of the largest global distributors of semiconductors and electronics compo nents. It specialises in supplying prototyping quantities for engineering design and new product development. TRX Electronics supplies electronic components from Mouser Electronics for delivery in South Africa, with local customer service and support.

For more information visit: www.trxe.com

JULY 2024 Electricity + Control

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