Electricity and Control April 2024

MEASUREMENT + INSTRUMENTATION

Circuit breaker test set The Doble TDR9100 Circuit Breaker Analyser is a state of-the-art circuit breaker test set for testing all types of circuit breakers with efficient and accurate performance measurements. The TDR9100 provides measurements for main and auxiliary contact timing, mechanical motion analysis, an alogue values, resistance and capacitance. This inclusive, rugged and field-portable instrument can be used for simple and complex testing of circuit breakers. The TDR9100 controls circuit breaker trip and close commands and supports the following operations: Trip (O), Close (C), Reclose (O-0.3s-C), Tripfree (CO), O-CO, O-0.3s-CO, First Trip (O), Slow Close (C). The TDR9100 test set offers: - Up to four breaks per phase, three motion chan nels and six event channels - Testing flexibility – the TDR9100 can be grouped as a set of two or three units, effectively doubling or wave for voltage is not maintained. One of the most rec ognised effects of harmonics in electrical systems is the excess heat they create in the conductors carrying them. This results in overheating in phase and neutral conduc tors, known as ‘triplen harmonics’. Unbalanced load The additional heat causes issues in cable runs, motor windings, and transformers. Overheating can cause signif icant damage or complete failure, either of which can lead to unplanned downtime and expensive repairs. A Fluke 1770 Series three-phase power quality analyser can be used to measure and diagnose harmonics. Benefits of power quality studies Once power quality studies reveal areas where energy is being wasted, a business can take steps to fix the issues. - Set up a preventive maintenance routine to ensure continuing measurement of energy use against the baseline benchmark. This means any issues can be noted as they arise. - Install harmonic filters on loads that add to the facili ty’s harmonic distortion. - Address the sources of unbalance. This may mean setting up a repair or replacement schedule for large motors with mechanical unbalance issues. - Mitigate unbalanced load issues. In some cases, this may mean adjusting single-phase loads to be more equally distributed across the phases. - Replace blown fuses where necessary. A blown fuse on a bank of three-phase power factor improvement capacitors could also cause the problem; simply re placing the fuse can resolve a major unbalance.

Monitoring power consumption with the Fluke 1777 three phase power quality analyser. Power quality studies highlight much of what can be done to save energy, reduce energy losses in a facility, and lower energy costs. Power quality monitoring will point to where the issues are coming from and how to fix them. Beyond the energy savings, power quality studies have been shown to lead to some additional benefits. For example: - Discovering potential failure points in assets that could cause major disruption allows for early remedi al work to be done - Mixed air temperatures can be corrected - Uncovering otherwise unrecognised faults such as improperly installed breakers prone to accidental tripping. □

Fluke is represented in South Africa by Comtest. For more information visit: www.comtest.co.za

MEASUREMENT + INSTRUMENTATION : PRODUCTS + SERVICES

tripling the usable channels and main contacts for up to 12 breaks per phase - User-friendly T-Doble software includes an intuitive control panel for quick, ef ficient and simple testing of circuit breakers - Measurement of additional parameters in the mechanism cabinet using Doble or third-party transducers. Using the TDR9100 test kit, electrical technicians will know that breakers can and will perform when they are needed. They can

Using the TDR9100 test kit, electrical technicians will know that breakers can and will perform when they are needed.

easily detect main contact and resistor contact timing errors. A patented digital rotary and linear transducer provide early diagnosis of mechanical problems. A further benefit is that testing is immune to Interference – the accuracy of test results is unaffected by severe conditions of electrostatic and electromagnetic interference normally present in harsh substation environments. The test set can be controlled using a Doble Universal Controller (DUC), tablet or PC. □

APRIL 2024 Electricity + Control

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