Leilang Electric delivers industry-leading 250kVA three-phase dry type zig zag grounding transformers, engineered to meet stringent ANSI/IEEE, CSA and DOE 2016 efficiency standards for North American power systems. Designed for 34.5kV primary voltage applications, this unit provides a reliable neutral grounding path to protect equipment and personnel during unbalanced loads or fault conditions. Featuring 100% copper windings for superior conductivity and a rugged NEMA 3R wiring compartment with tamper-proof housing, it ensures long-term dependable performance in both indoor and outdoor industrial environments.

Our zig zag grounding transformers are purpose-built to create a stable neutral point in ungrounded three-phase systems, effectively limiting overvoltages and enabling proper ground fault protection. The Zn vector group configuration optimizes zero-sequence current handling, with a precisely calibrated neutral impedance of 47.5 ohms to ensure reliable fault detection and system stability. Every unit is certified to meet ANSI/IEEE C57 standards, CSA requirements and DOE 2016 efficiency regulations, guaranteeing seamless integration into North American power grids.

Constructed with 100% copper windings, this transformer delivers exceptional electrical conductivity, lower heat generation and extended service life compared to aluminum alternatives. The Class F insulation system (rated for 180°C) combined with a 115°C temperature rise provides a generous thermal safety margin, ensuring reliable operation even under continuous full-load conditions. The AA (self-cooled) design eliminates the need for forced cooling systems, reducing maintenance requirements and improving overall system reliability.

Housed in a heavy-duty steel enclosure with a NEMA 3R rated wiring compartment, this transformer offers protection against rain, snow, dust and physical damage. The tamper-proof housing with hinged, pad-lockable front compartment doors enhances security in public or unattended locations. Additional safety features include a penta-head bolt entry assembly and a hot stick included for safe high-voltage maintenance operations. The dry type cast resin construction eliminates fire and environmental hazards associated with oil-filled transformers.

All Leilang Electric grounding transformers undergo comprehensive factory testing to ensure compliance with international standards. Each unit is subjected to winding resistance tests, insulation resistance tests, voltage ratio error tests, short-circuit impedance tests, no-load and load loss tests, induced voltage withstand tests, separate source voltage withstand tests and pressure integrity tests before shipment.

Q: What international standards does the 250kVA zig zag grounding transformer comply with?

A: Our transformer fully meets ANSI/IEEE power transformer standards, CSA safety requirements and DOE 2016 efficiency regulations, ensuring compliance with North American electrical codes.

Q: What is the primary function of a zig zag grounding transformer?

A: It creates a stable neutral point in ungrounded three-phase systems, providing a path for zero-sequence currents during unbalanced loads or ground faults, protecting equipment and enabling proper fault protection.

Q: What material are the windings made of, and what are the benefits?

A: Both primary windings are constructed from 100% copper, offering superior electrical conductivity, lower heat generation, better corrosion resistance and longer service life than aluminum windings.

Q: What is the enclosure rating, and where can it be installed?

A: It features a NEMA 3R rated wiring compartment with a tamper-proof, pad-lockable steel enclosure, making it suitable for both indoor and outdoor installations in industrial and utility environments.

Q: What cooling system does this transformer use?

A: It utilizes an AA (self-cooled) natural air cooling system, eliminating the need for fans or pumps, reducing maintenance requirements and improving overall system reliability.

Q: What warranty and customization options are available?

A: We offer a 24-month warranty from the bill of lading date with free replacement of defective accessories. Full OEM/ODM customization is available, including custom voltages, colors and branding.