Electricity + Control July 2015

DRIVES, MOTORS + SWITCHGEAR

Protection and control for three phase LV motors The modular MA electronic motor protection relay from NewElec , controls, monitors and protects the performance of 3-phase LV motors.The relay measures electrical motor variables such as current, phase unbalances, phase loss, earth leakage, earth fault, short circuit and voltage condi- tions. It can be used as either a standalone electronic motor

protection relay or as part of an automated process communi- cating to a PLC. De- signed for advanced motor protection, the MA comes complete with integrated cur- rent transformers and

earth leakage core in the range from 0,5 to 250A.The current range can be extended using interposing CTs. Individual fault status indication is provided by LEDs for easy diag- nostics. It also stores the last four faults with time and date stamping. The relay has five digital inputs and four output contacts (two are programmable).The inputs will accommo- date voltages from 24 to 220 Vac or dc, and for this reason, it is an ideal choice for rapidly automating older plants utilising the customer’s existing switchgear and optimising the electrician’s circuit knowledge. Enquiries: Email sales@newelec.co.za Soft starter for electric motors TELE has introduced a new 3PH soft starter with true 3 ph control and integrated current control for a nominal motor power 2,2 kW up to 22 kW. The unit is thyristor based and integrates current measurement and current limiting without external components and wiring.This function controls and limits exactly the maximum motor current that is used to start the whole system without overloading the motor and drive mechanics. Additional power peaks and flickers in the mains are reduced to a minimum, so the stability of the sup- ply is much higher compared to star/delta or direct motor starters. The overall size of the new MS3 is very compact and saves space in the cabinet.The fan-less design improves time between maintenance. Asynchronous motors are the most common drive type in machinery, automation, HVAC, pumps and transport busi- ness. Direct starting these types of motors causes a high inrush current, mechanical stress and destabilisation of the

MAKING POWER PERFORM

JWT66568

For more info contact us on (011) 706 7184 or e-mail: info@powertech.co.za manufacturers of electrical and electronic equipment. Our wide range of products and systems integration skills provide a total design, manufacture, supply, and installation solution. Power brings dreams to life and turns opportunity into reality.Wherever there is electricity, there’s a human being who’s empowered in some way, and that’s what we at Powertech strive for. A subsidiary of the Altron Group, we are one of Southern Africa’s leading

mains. Using soft starters to start the motor, eliminates or at least minimises those dis- advantages and guarantees a long lasting and low mainte- nance operation system. Enquiries:Tel. 011 454 8053 or email edwin@vepac.co.za

www.powertech.co.za