Three-phase current measurement

November 2009 Maintenance, Test & Measurement, Calibration

LEM introduces triple current measurement in single housing.

LEM has introduced the HTT series of PCB-mounting current transducers to provide the facility to measure three currents with a single PCB-mounted unit. The new transducers, with maximum measurement currents ranging from 25 to 150 A(RMS), allow three-phase currents to be monitored independently by a compact unit with a height of only 29 mm.

The HTT transducers have three 12 x 10 mm apertures for the primary conductors and are securely mounted by four metallic pins, which are soldered to the PCB. Secondary connections for power supply, 0 V and the three voltage outputs are also made to the PCB by pins.

Five different models using the same housing are available to cover nominal current measurements of 3 x 25, 50, 75, 100 or 150 A, working from a bipolar power supply of ±12 to 15 V. The use of open-loop Hall-effect technology allows DC, AC or pulse currents to be measured and provides galvanic isolation between the primary and output circuits, withstanding a test isolation voltage of 2,5 kV/ 50 Hz/1 min. The transducers conform to the EN 50178 standard and are CE marked according to European Directive 2004/108/EEC. They are particularly suitable for industrial applications and home appliances, such as variable speed drives, UPS, SMPS and airconditioners.

Further reading:

Mini data loggers for temperature and humidity monitoring
Maintenance, Test & Measurement, Calibration
Testo’s range of four compact data loggers covers temperature and humidity monitoring for storage, refrigeration and transport applications, with USB-C or Bluetooth connectivity and capacity for up to 16 000 readings.

Read more...

---

Alternative fuels for cutting, brazing, soldering and heating
Maintenance, Test & Measurement, Calibration
Bolt and Engineering Distributors, as an authorised distributor for the Harris Products Group, is helping South African industries transition from acetylene to safer, more cost-effective alternative fuels for cutting, brazing, soldering and heating applications.

Read more...

---

Rethinking corrosion protection in process plants
Omniflex Remote Monitoring Specialists Maintenance, Test & Measurement, Calibration
Remote monitoring is changing how cathodic and anodic protection systems are managed in process plants, giving operators continuous visibility of corrosion protection performance and enabling more proactive maintenance decisions.

Read more...

---

Installation safety tester
Vepac Electronics Maintenance, Test & Measurement, Calibration
A combination measuring device for testing electrical installations, offering safety tests including RCD, voltage, loop, low-resistance, earth resistance and insulation checks via a 3,5-inch TFT colour display.

Read more...

---

Bringing predictive maintenance to the next level in the pulp and paper industry
Maintenance, Test & Measurement, Calibration
ennomotive has launched an international competition seeking innovative predictive maintenance solutions for conveyor belt systems, addressing a real operational challenge faced by pulp and paper company CMPC.

Read more...

---

Linear regulated 2-channel laboratory power supply
Vepac Electronics Maintenance, Test & Measurement, Calibration
Vepac Electronics offers a dual-channel laboratory power supply built for safe, precise testing in laboratories and workshops.

Read more...

---

When oil gets old
Wearcheck Maintenance, Test & Measurement, Calibration
WearCheck explains how oxidation breaks down lubricating oils over time, and how routine oil analysis can catch the warning signs before equipment failure.

Read more...

---

SEW-EURODRIVE brings intelligent energy optimisation to Electra Mining
SEW-EURODRIVE Maintenance, Test & Measurement, Calibration
At Electra Mining Africa 2026, SEW-EURODRIVE will showcase its DriveRadar IoT platform for predictive maintenance and real-time energy optimisation, alongside plant energy surveys and an 1850 kW medium voltage motor display.

Read more...

---

Thermal imaging camera with high thermal resolution
Vepac Electronics Temperature Measurement Maintenance, Test & Measurement, Calibration
Vepac Electronics introduces a compact thermal imaging camera that helps technicians spot temperature problems before they become costly failures.

Read more...

---

What your lubricant really costs
Maintenance, Test & Measurement, Calibration
The purchase price of an industrial lubricant is only a fraction of what lubrication truly costs a business. Lubrication Engineers South Africa explains how shifting from unit price to total cost of ownership changes the equation significantly.

Read more...

---