Electricity + Control September 2019

round up

DRIVES, MOTORS + SWITCHGEAR

Motor protection and detecting cable theft

information, including when the alarm was activated and how long it took for someone to respond. The system needs to be re- set at the location of the alarm in order to confirm response by security.When the re- set function is activated, the unit logs the date and time of the response.” The protection system works on 220 V or 110 V power and can also be used to monitor cable without power. A battery backup for SMS communication provides backup power for up to eight hours. Proloc and ProBeck electronic relays for motors (380 V, 400 V, 525 V, 950 V and 1 100 V – 3.3 kV and 6.6 kV) provide for thermal overloadprotection, earth insulation lockout, frozen or vacuum contact failure and earth leakage protection. Other use- selectable features include short circuit, frequency and power factor meas urement as well as minimum load, over voltage and under voltage protection. Becker protection relays are also used to control pumps and motors based on water levels, valve position, temperature sensors, time of day and moisture content of the soil. They can detect dry run in boreholes, tanks and dams and can be programmed to re-start pumps automatically after a specified time or at a set level.

A key safety feature is the door- mounted infra-red link that enables a laptop, with Proloc software, to be used to manage all settings and downloads so personnel do not have to open the panel door and expose themselves to dangerous live equipment. Enquiries: Becker Mining South Africa. Tel: +27 (0)11 617 6300, or email: info@za.becker-mining.com Proloc and ProBeck low voltage electronic protection and control relays provide for motor protection and can detect cable theft.

Becker Mining South Africa’s Proloc and ProBeck electronic protection and control relays are designed for motor protection and to detect cable theft.They can be used in diverse industries, including mining and quarrying, electrification, water and wastewater, chemical, petrochemical and general engineering, as well as municipalities. Nico de Lange, Vice President: Operations & Systems at Becker Mining South Africa says, “Becker’s low voltage relays, which incorporate advanced technologies to provide dependable protection of electric motors used on pumps, fans, conveyors and compressors, can also be used as highly effective stand-alone cable protection systems, to guard against cable theft. The relays are programmed to detect cable theft by identifying a change in impedance of cable, up to 1 100 V, connected to a motor or pump. “In the event of cable tampering, the unit sends an SMS or activates an emergency alarm or siren. The system can provide SCADA visualisation and communicate relevant information to a control room via an existing PLC. “It can log up to 1 400 events with real time and date and providing critical

Electrical switchgear for mining mill expansion

Gauteng based JB Switchgear Solutions was recently awarded a contract for the design, manufacture and supply of a range of electrical switchgear equipment to Gold 1 – New Kleinfontein Gold Mining Company’s Mill Expansion Project at its Modder East operations. The scope of the contract included a number of 525V-rated containerised motor control centres (MCCs), an 11 kV containerised switchboard and extension panel, as well as power and lighting transformers. In this instance, JB Switchgear’s popular Eagle series panel design was used for the 525 V MCCs. It is a robust, user-friendly system that carries IEC 61439-1/2, SANS 1973-1 and IEC/TR 61641 certification, and over 30 000 tiers have been installed on sites around the world. Starter sizes ranged between 0.55 kW and 75 kW and variable speed drives ranged from 45 kW to 200 kW. The project essentially includes a new ball mill, a new elution plant and an extension of the existing carbon-in-leach (CIL) plant. The 11 kV ball mill motor is rated at 3.3 MW.

Enquiries: Johan Basson at JB Switchgear Solutions. Tel: +27 (0)11 027 5804, or email: info@jbswitchgear.co.za

The contract included supply of a number of 525 V-rated containerised motor control centres.

Electricity + Control

SEPTEMBER 2019

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