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This guide provides recommendations for loading mineral-oil-immersed transformers and step-voltage regulators with insulation systems rated for a 65 °C average winding temperature rise at rated load. This guide applies to transformers manufactured in accordance with IEEE Std C57.12.00 and tested in accordance with IEEE Std C57.12.90, and step-voltage regulators manufactured and tested in accordance with IEEE Std C57.15. Because a substantial population of transformers and step-voltage… read more regulators with insulation systems rated for 55 °C average winding temperature rise at rated load are still in service, recommendations that are specific to this equipment are also included. read less

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The recommendations presented in this guide primarily apply to new large oil-immersed power transformers with high-voltage windings rated 69-287 kV inclusive. However, appropriate sections of the guide may be applied to lower voltage transformers when similar conditions and similar transformer construction exist, and may also be used in servicing older transformers which have been opened for maintenance or repair work. Increasing application of larger capacity high-voltage transformers with… read more reduced insulation has brought forth the parallel need for increasing care during installation and service. To maintain dielectric strength of the insulation it is essential to avoid moisture and entrapped air or gas bubbles. Since oil is an essential portion of the insulation structure, oil quality and care in handling are extremely import ant . read less

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1 Scope 1.1 This Standard applies to complete flue-connected, oil-fired service water heaters that are provided with automatic control devices. These service water heaters may be used both for heating and for supplying of domestic hot water. They are

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This guide covers the selection and procedures for electrical cables and cable systems installed in hazardous (classified) locations on oil and gas land drilling rigs.

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