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Daniel Brown
Daniel Brown
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Daniel BrownMiembro
For a lab-scale step from coarse nut paste to an ultra-fine 3-5 mil (~75-125 µm) grind, a small rotor-stator colloid mill is appropriate. In the GlobeCore lineup, the practical «lab/pilot» choice is a CLM-100.2 class unit (compact footprint, adjustable rotor-stator gap), run in a recirculation loop so you can make multiple passes until you hit your particle-size target without overloading the head.
enero 27, 2026 a las 7:31 pm en respuesta a: Efficiency of power transformer when maximum transfer of power occurs is? #332307Daniel BrownMiembroTheoretical maximum power transfer happens at ~50% efficiency (when load resistance equals source resistance), but power systems do not operate there. Grid transformers are optimized for high efficiency (98-99%+), not for theoretical max transfer.
enero 26, 2026 a las 12:24 pm en respuesta a: Why is a power factor test of a transformer carried out during diagnostics? #332037Daniel BrownMiembroPower factor (tan-delta) testing measures dielectric losses and insulation health. Rising power factor indicates moisture, aging, or contamination. Utilities use it for condition-based maintenance.
enero 25, 2026 a las 7:57 pm en respuesta a: Why are underground power transformers used in urban areas? #331908Daniel BrownMiembroUnderground pad-mounted transformers reduce visual impact, improve public safety, and protect against weather and vandalism. They enable high-density distribution in cities and commercial zones.
enero 24, 2026 a las 1:21 pm en respuesta a: What procedure is used for power transformer testing? #331673Daniel BrownMiembroSequential routine, type, and special tests per IEC/IEEE include electrical, dielectric, mechanical, OLTC, and oil diagnostics.
enero 24, 2026 a las 6:40 am en respuesta a: Why are residential power transformers used in low voltage distribution? #331609Daniel BrownMiembroResidential power transformers (pole or pad-mounted) step down medium voltage feeders to safe utilization levels (typically 120/240 V). They provide isolation, regulation, and fault withstand capability for neighborhoods. Their oil-filled or dry-type construction withstands outdoor environments and overload surges.
enero 23, 2026 a las 5:03 pm en respuesta a: What determines power in transformer cores during operation #331506Daniel BrownMiembroPower in the core is associated with core losses: hysteresis and eddy currents. These depend on core material, lamination thickness, flux density, and operating frequency. Higher flux density and frequency increase losses and heating. The applied voltage and turns per leg set flux levels, so designers choose a compromise between core size and loss. Although the core does not «deliver» power externally, its loss power becomes heat that must be removed by the cooling system.
enero 23, 2026 a las 2:28 am en respuesta a: What testing procedures are used in power transformer manufacturing to verify insulation and thermal performance? #331375Daniel BrownMiembroManufacturers perform induced and separate-source voltage tests, lightning and switching impulse tests, tan-delta, PD tests, heat runs, temperature rise tests, and DGA baseline.
enero 22, 2026 a las 8:55 pm en respuesta a: What materials are used for power transformer cores? #331333Daniel BrownMiembroLaminated grain-oriented silicon steel or amorphous metal to reduce hysteresis and eddy losses.
enero 22, 2026 a las 8:47 am en respuesta a: What does a power factor test on a transformer measure? #331211Daniel BrownMiembroIt measures insulation loss characteristics under AC stress. The test quantifies how much real power is dissipated in the insulation versus reactive energy storage. Trending PF over years reveals gradual insulation aging, moisture uptake, or partial discharge precursors, aiding condition-based maintenance.
enero 22, 2026 a las 3:29 am en respuesta a: What are the key components included in a standard TSS system? #331135Daniel BrownMiembroA typical TSS setup includes two automatic valves that attach to upper and lower transformer ports, an oil level sensor that tracks thresholds, a set of power and signal cables, and a centralized control cabinet. These components work together to accurately detect and respond to unsafe oil processing conditions.
enero 22, 2026 a las 2:27 am en respuesta a: What does an AC power transformer do in mains power systems? #331121Daniel BrownMiembroIt enables voltage adaptation and efficient distribution by stepping voltages up or down while ensuring insulation and safety margins.
enero 21, 2026 a las 11:48 pm en respuesta a: What does a power transformers test assess before commissioning? #331083Daniel BrownMiembroIt assesses ratio accuracy, polarization, insulation integrity, impedance, losses, cooling performance, and bushings condition to ensure compliance with factory guarantees and grid specifications.
enero 21, 2026 a las 2:22 pm en respuesta a: What limitations or risks exist when using LFD on large transformers? #330941Daniel BrownMiembroWhen using LFD on large transformers, the main limitations are related to power availability, process duration, and thermal control. Very large windings require high currents and long drying times, sometimes many days. There is a risk of uneven heating or local overheating if temperature monitoring is poor, which can damage cellulose. Mechanical stresses from thermal expansion and the need for a reliable deep vacuum system are also critical factors. Proper control and experienced operation are essential to avoid insulation degradation.
enero 21, 2026 a las 12:34 pm en respuesta a: Why is heat generated directly in the windings themselves, and how does this affect the moisture removal process? #330899Daniel BrownMiembroHeat is generated directly in the windings because the low-frequency current flows through the copper conductors and produces I²R losses inside the metal itself, not in the surrounding air or oil. This means the thick paper insulation is heated from the inside outward, exactly where most of the moisture is trapped. As a result, a strong temperature and vapor-pressure gradient is created inside the insulation, which drives moisture toward the surface much faster and makes vacuum removal far more effective than external heating methods.
enero 21, 2026 a las 7:48 am en respuesta a: What should the actual curing time be during the production of modified bitumen, and how does it change when using different modifiers? Which standard governs this? #330830Daniel BrownMiembroThere is no single «correct» curing time that applies to all modified bitumens, because it depends mainly on the type of modifier, its concentration, temperature, and mixing/shear conditions. For SBS-modified bitumen, typical digestion times are in the range of 1 to 3 hours at 170-180 °C, until swelling and phase inversion are complete. For EVA or PE modifiers, curing is usually shorter, often 30-90 minutes, because the mechanism is mainly dispersion rather than swelling. Sulfur-modified systems may require an additional holding period to complete crosslinking. There is also no single international standard that fixes curing time. The process is governed indirectly by performance standards such as EN 14023 (PMB specification), ASTM D6164, and national PMB specs, which define final properties (elastic recovery, softening point, storage stability), not the digestion time itself. In practice, curing time is validated by property stabilization and storage stability tests, not by a fixed number in a standard.
enero 21, 2026 a las 4:16 am en respuesta a: What topics does Electric Power Transformer Engineering by James H. Harlow cover? #330779Daniel BrownMiembroHarlow’s reference spans design, materials, dielectric systems, OLTC, cooling, testing, maintenance, protection, diagnostics, failure analysis, and utility specifications.
enero 20, 2026 a las 11:09 pm en respuesta a: Can the TOR-5 online monitoring system provide measurements of the transformer insulation condition? #330706Daniel BrownMiembroTOR-5 does not measure the insulation condition directly in the way a laboratory test would, but it provides continuous indirect indicators that are very sensitive to insulation health. Parameters like moisture in oil, water activity, hydrogen, temperature, and trends reflect the state of the oil-paper system and its aging dynamics. From these trends you can assess whether the insulation is drying, aging, or deteriorating. For a direct assessment of paper condition (for example DP), offline tests such as furan analysis are still required, but TOR-5 is very effective for continuous condition tracking.
noviembre 7, 2025 a las 8:26 pm en respuesta a: Kindly share with me a quote for CMM-4T. Kindly treat it as urgent. Re: GlobeCore #327150Daniel BrownMiembroThe CMM-4T is a transformer oil purification unit designed for turbine and transformer oil treatment at 4 m³/h. It performs dehydration, degassing, and filtration. We will prepare an urgent quotation including price, technical specifications, and delivery terms.
noviembre 7, 2025 a las 7:16 am en respuesta a: Please information about online transformer oil purification system #327088Daniel BrownMiembroGlobeCore produces online oil purification systems (CMM-MSD) that continuously dry and degas transformer oil without shutdown. Please specify transformer type and oil volume for technical details.
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