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Megan Young
Megan Young
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一月 27, 2026 6:14 下午 回复至： Why should we use star-delta connection in step down power transformers? #332297
Enables phase shift, neutral availability, reduces harmonics, and suits LV distribution.
Vector group describes phase displacement, winding configuration (Y/D/Z), and connection (HV/LV). It informs parallel operation, harmonic behavior, and protection settings. Common groups include Dyn11, YNd1, Yy0.
Load currents increase copper (I²R) losses and stray losses. Thermal rise accelerates oil aging and insulation degradation, raising dielectric losses.
一月 25, 2026 8:08 上午 回复至： What topics are covered in electrical power, motors, controls, generators, and transformers? #331819These industrial texts integrate machinery, controls, and power conversion. Transformer sections cover voltage transformation, impedance, losses, vector groups, cooling, and protection within broader plant power systems.
The secondary winding has more turns than the primary, boosting voltage while current decreases proportionally to conserve apparent power minus losses.
Ratings include voltage class, kVA/MVA, cooling type (ONAN/ONAF/ODAF), impedance, insulation class, and temperature rise. They follow IEC/IEEE catalog ranges.
Medium power transformers (typically 5-60 MVA, MV/HV interfaces) are installed in sub-transmission and distribution substations. They reduce transmission voltages to feeder voltages for industry and cities, forming a key intermediate step between bulk transmission and final distribution.
一月 20, 2026 11:54 上午 回复至： Where are power distribution transformers installed in electrical networks? #330534Distribution transformers are installed on poles, pad-mounted enclosures, vaults, and kiosks to step MV feeders down to LV service for homes, commercial buildings, and industry.
Cost is driven by kVA/MVA rating, voltage class, insulation level, cooling system, and special features like OLTCs, online monitoring, and seismic or fire requirements. Copper and core steel market prices significantly influence base cost. Custom vector groups, multiple windings, higher efficiency (low-loss) designs, and stringent test requirements add expense. Logistics, such as transportation constraints, site access, and installation complexity, also factor into the total procurement price seen by industrial customers.
Control power transformers feed relays, PLCs, contactors, and meters in automation, switchgear, and motor control centers, ensuring stable low-voltage auxiliary power.
Common cooling methods include ONAN (oil natural air natural), ONAF (oil natural air forced), OFAF (oil forced air forced), and OFWF (oil forced water forced). Dry-type units use AN (air natural) or AF (air forced). Radiators, fans, oil pumps, and heat exchangers enhance heat removal and allow higher loading. Some large units use directed oil flow and internal ducts to manage winding hotspots. Cooling class is a key specification, directly influencing kVA rating and overload capacity.
一月 19, 2026 9:21 下午 回复至： How is power factor for a transformer corrected in industrial facilities? #330408Capacitor banks or synchronous condensers offset magnetizing reactive power, improving PF at light loads and reducing demand charges.
Apparent power for single phase is S=VI; for three phase S=?3VI. Real power depends on power factor and losses.
For high-capacity transformer networks, the CMM-12 and CMM-24 systems are optimal. They provide degassing, drying, and purification for oils in transformers up to 100 MVA. Technical specifications and delivery schedule will be included.
The TOR-80, TOR-2, and TOR-3 analyzers are available for immediate production. Each device complies with IEC standards. We will provide detailed pricing, delivery time, product documentation, and packing information. The Reid vapor pressure unit can be offered separately upon confirmation of specification.
GlobeCore filtration plants remove moisture, gases, and mechanical impurities from transformer oil, improving breakdown voltage and dielectric strength. We’ll send specifications and price details.
十一月 9, 2025 2:30 下午 回复至： Looking to purchase a TOR-3 Tan Delta Tester for transformer oil and dielectric fluids. #327310The TOR-3 measures the dissipation factor (tan delta) of transformer oil and dielectric fluids in accordance with IEC standards. We will assist with the purchase process and provide technical documentation and pricing.
十一月 9, 2025 12:56 下午 回复至： Need the cost of purchasing the CMM-24R/10000 Type H and estimated delivery charges. #327304The CMM-24R/10000 Type H is a high-capacity oil regeneration plant operating at 24 m³/h. We’ll send pricing, delivery time, and transport cost estimates.
Oil filtering removes solid particles that cause wear and clog systems. GlobeCore units provide 3-5 stage filtration down to 1 �m – ideal for extending oil and equipment life in manufacturing, power, and transport industries.
It includes heating, coarse filtration, vacuum drying, fine filtration, and degassing. GlobeCore automates all stages in one system – restoring BDV above 70 kV and removing water to <10 ppm.
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