Dry type transformer installation and use instructions

Use Environment & Operating Conditions

• Altitude & Temperature: Installation altitude shall not exceed 1000 meters; ambient temperature shall not exceed 40°C (customized designs are available for exceeding this limit).
• Humidity Range: The operating environment allows for up to 100% relative humidity, with a temperature range of -25°C to +40°C (compatible with on-load switches and temperature controllers at -25°C).
• Installation Site: Primarily designed for indoor use, requiring a clean environment free of electrical dust and corrosive gases, with adequate ventilation. For poorly ventilated locations (e.g., basements), forced ventilation is recommended—requiring approximately 3-4 m³/min of ventilation per 1kV loss (sum of no-load and load loss).
• Installation Clearance: A minimum distance of 800mm from walls and other obstacles is required; adjacent transformers should be spaced at least 300mm apart. These distances can be adjusted appropriately for space-constrained settings such as distribution boxes.
• Fixing Requirements: Under normal circumstances, the transformer can be placed directly on the installation site and commissioned after installation and inspection. For anti-vibration needs, foundation bolts should be embedded, and the transformer secured with bolts and nuts.

Key Specifications & Technical Parameters

Note: IP20 enclosures prevent the entry of solid foreign objects larger than 12mm and provide a safety barrier for live parts. IP23 enclosures build on IP20 protection, adding resistance to water droplets falling at a 60° angle from the vertical.

Product System Description

Temperature Display & Control System (Optional)

• Functions: Delivers overload alarm signals and real-time temperature readings automatically.
• Protection Actions: Triggers fan start/stop, power tripping, and transformer disconnection when the internal coil temperature exceeds the preset limit.

Cooling System

• Natural Air Cooling (AN): Supports 100% rated output capacity.
• Forced Air Cooling (AF): Enables 25% long-term overload and 50% short-term overload.

Protection Configuration

• Standard Configuration: IP00 (indoor use without casing).
• Optional Configurations: IP20 or IP23 casings (note: derated operation should be considered for transformers with high protection classes to ensure performance).

Packaging & Transportation

• Packaging Types: Available in open type (without protective cover) and protected type (with protective cover). Controllers, air-cooling devices, and outdoor shields are packaged separately or as a whole unit.
• Transportation Modes: Typically transported by railway, waterway, or road; lifting and unloading can be performed using cranes, winches, or other appropriate machinery.
• Weather Protection: During transportation, the product must be covered with a rainproof cloth to prevent water damage.
• Lifting Guidelines: For packaged products, ropes should be attached to the sleepers at the four corners of the bottom of the packaging box. For unpacked products, use specialized lifting equipment—lift 100mm-150mm off the ground for initial inspection before formal lifting.
• Transportation Conditions: Transport routes should have no slopes exceeding 15°. The product’s center of gravity must align with the vehicle’s vertical centerline to ensure even load distribution. The long axis of the product should match the transportation direction, and the unit must be firmly secured to prevent displacement or tipping.
• Crane-Free Handling: When lifting without a crane, ensure compliance with safety technical requirements and verify that the lifting capacity matches the product’s transport weight.
• Trolley-Equipped Products: Trolleys with rollers (if requested by the user) are removed during transportation to ensure stability. After arrival, reinstall the trolley before installation. Roller shafts at both ends of the frame can be rotated 90° to allow horizontal or vertical movement of the product.
• Post-Delivery Storage: Minimize storage time in the transportation state (especially outdoors). Before installation, store the product in a covered, dry, and well-ventilated area, and take measures to protect it from mechanical damage and contamination.

Inspection & Acceptance

• Upon receiving the product, users should promptly unpack and inspect it to verify the completeness of items listed in the packing list, check for transportation damage, component displacement, loose fasteners, insulation damage, and coil surface contamination.
• Confirm that the data on the product nameplate (capacity, voltage level, connection group, short-circuit impedance, etc.) matches the ordered specifications.
• Verify the completeness of factory technical documents.
• If the product is not commissioned immediately after unpacking, repackage it and store it in a secure indoor location to prevent theft or damage.
• Sign a handover document with the transportation department, clearly documenting any issues identified during inspection.

Pre-Installation Visual Inspection

• After unpacking, remove protective devices (if applicable) to inspect the external condition, with special attention to the mechanical integrity of coils and iron cores, coil and core compression, and the tightness of external connection bolts.
• Re-tighten all fasteners and coil/core compression components in sequence after inspection—no looseness is permitted.
• Disassemble, reset, and install components on the transformer body in accordance with factory technical requirements and component instructions.
• Clean dust and dirt from the product using dry compressed air or clean rags (avoid volatile cleaners).
• If the product has been stored for an extended period and shows signs of condensation or water droplets on the surface, dry it until the coil insulation resistance meets the qualified standard.

Pre-Commissioning Tests

Grid Operation

• After the auxiliary protection devices and monitoring systems are properly grounded and qualified, the transformer should first undergo no-load operation. The protection system should be checked and adjusted after three closing tests.
• The high-voltage side tap positions are set to the rated value at the factory. For voltage adjustment (no-excitation voltage regulation), cut off the transformer power supply first, then adjust the tap connections in accordance with the tap voltage indicated on the product nameplate.
• The transformer is equipped with a BWDK series thermostat, with temperature-sensing elements embedded in the upper end of the low-voltage coils. It automatically detects and displays the operating temperature of each three-phase coil. When the coil temperature reaches the design threshold, the thermostat automatically starts/stops fans, triggers alarms, or trips the power supply. The set temperature can be adjusted by the user in accordance with the thermostat manual.

Maintenance

• Inspect coils, iron cores, binding wires, tap terminals, and fasteners for damage, deformation, looseness, discoloration, overheating marks, or corrosion. Identify the cause of any abnormalities and take appropriate corrective measures.
• Remove dust from the transformer: Wipe accessible parts with a dry cloth (avoid volatile cleaners). Use compressed air to blow off dust from hard-to-reach areas inside the iron core and coils.
• For transformers equipped with fans: Clean dust and debris from the fans (take care not to damage or deform the fan blades), check the fan bearing grease, and replenish or replace it as needed.
• Before recommissioning the transformer after maintenance, carefully inspect to ensure no metal or non-metallic foreign objects are left in the coils, iron cores, or insulation components.

Safety Precautions

• The power supply for the temperature controller (and fans) should be sourced from the switchboard, not directly connected to the transformer.
• Before commissioning the transformer, inspect the transformer room’s grounding system to ensure it meets safety requirements.
• Keep the transformer casing door closed to ensure electrical safety.
• Install measures to prevent small animals from entering the transformer room to avoid accidents.
• Staff must wear insulating shoes when entering the transformer room, maintain a safe distance from live parts, and refrain from direct contact with the transformer.
• If sudden increases in transformer noise are detected, immediately monitor the transformer’s load condition and grid voltage, strengthen temperature change observations, and consult relevant professionals promptly.
• Conduct a comprehensive inspection of the transformer every 3-5 years, and perform preventive tests as needed.
• Installation, testing, operation, and maintenance of the transformer must be carried out by qualified professionals.