100kVA Single Phase Pad Mounted Transformer

Product Overview

The 100kVA Single Phase Pad Mounted Transformer provides a ground-level transformation point between an underground medium-voltage feeder and a compatible low-voltage single-phase service. Zisheng Electric coordinates the proposed design with the purchaser’s utility specification, load study and cable interfaces. A 100kVA nameplate rating does not establish the voltage combination, loss level or protection package.

Choosing 100kVA for the Load

100kVA is apparent power. At a power factor of 0.8, it corresponds mathematically to 80kW before allowances for starting duty, harmonics, environmental conditions and the actual operating profile. It provides approximately 33.3% more rated apparent-power capacity than 75kVA. A capacity increase does not correct an incompatible voltage or phase arrangement.

For a specified 240V single-phase output, 100,000VA divided by 240V gives approximately 416.7A of rated secondary current. This calculation is specific to that voltage; it is not a cable, terminal, fuse or breaker selection. Review the connected conductor range, terminal details, neutral loading and available fault current before approving the interfaces.

Where heat pumps, electric water heating or vehicle charging are planned, distinguish diversified demand from connected ratings and assess coincident operation. A managed charging arrangement may change the demand study, but any controls and operating limits must be defined by the project designer.

Secondary Loading and Installation

For a center-tapped secondary, specify both end-to-end and line-to-neutral service voltages. Review the maximum loading of each winding section, expected imbalance and neutral requirements with the selected design. Do not assume the entire transformer rating can be drawn from one half of a split-phase winding.

Coordinate the foundation footprint, anchoring, underground openings, cable bending space, door swing, working clearance, drainage and lifting access before civil work. The approved drawing establishes dimensions; enclosure size and weight must not be copied from another capacity.

Feed Arrangement and Protection

A dead-front interface uses screened, insulated cable connections. Match connector voltage class, current rating, bushing interface and parking provisions as a system. Radial feed normally terminates an incoming circuit; loop feed provides incoming and outgoing interfaces. Switching, isolation and fault interruption depend on the specified equipment, protection coordination and utility operating procedures.

Core and Windings

Select the core, winding conductor, insulation and mechanical support together for the agreed duty. Copper or aluminum may be requested subject to engineering confirmation. Compare guaranteed no-load losses, load losses, impedance and temperature rise rather than judging performance by conductor material alone.

Insulation and Cooling

ONAN means Oil Natural Air Natural: natural oil circulation transfers heat to the tank and surrounding air without cooling fans. Confirm this designation with the proposed mineral-oil design. An ester-fluid option requires a separate review of thermal performance, insulation and site requirements.

BIL means Basic Impulse Insulation Level, the specified lightning-impulse withstand level. Coordinate BIL, power-frequency withstand, cable terminations and surge protection with the actual system voltage; a 100kVA rating does not establish these values.

Environmental Conditions

Provide site altitude, maximum and minimum ambient temperatures, humidity, salt exposure, flood risk and seismic requirements. Coastal, high-altitude and unusually hot locations require a review of insulation, thermal design, coating and foundation conditions.

Standards and Customization

State the destination utility specification and applicable standard with its edition in the inquiry. For an ANSI/IEEE design, agree the relevant IEEE C57 requirements for the transformer, enclosure and tests. A standards reference describes a design requirement; product certification and market-specific efficiency compliance require separate evidence for the offered configuration.

Product Features

• 100kVA single-phase capacity for a documented underground distribution load schedule.
• Ground-level enclosure and cable entry coordinated with the approved foundation drawing.
• Primary and secondary service voltages selected to match the utility and connected loads.
• Radial or loop interfaces and dead-front connections reviewed as part of the network design.
• Protection, grounding and accessory scope defined in the order documentation.

Technical Guidance

Provide the maximum diversified kVA demand, power factor, starting loads, harmonic sources and planned expansion. Include the utility one-line diagram, primary system and winding voltages, secondary service arrangement, frequency and grounding requirements.

For split-phase service, provide the line-to-neutral load schedule and expected imbalance. Coordinate connector classes, primary and secondary current ratings, fault duty, fuse selection, surge protection and grounding with the utility and installer. A larger transformer may require revised cable ratings and protection settings.

Approve the data sheet, general arrangement, terminal diagram, guaranteed performance schedule and accessory list before manufacture. Confirm the foundation and cable opening arrangement before concrete work. The approved technical documents define the supplied configuration.