The appearance of dry-type transformers varies due to differences in design, application, and manufacturing processes, but they typically feature the following typical characteristics while allowing for customization based on specific needs. Below is a detailed introduction to their appearance:

　　I. Basic Appearance Features

　　1. Structural Form

　　Box-type (Enclosed): The outer casing is made of metal or non-metal materials, fully enclosing the transformer body with a protection rating of IP23 or higher, suitable for environments with high dust and humidity levels (e.g., factories, underground substations).

　　Open-type: No outer casing or only partial protection is provided, offering better heat dissipation performance but lower protection ratings, primarily used in dry and clean indoor environments (e.g., office buildings, commercial centers).

　　2. Color and Material

　　Outer Casing Color: Common colors include gray, white, or blue, with some customized models adopting corporate standard colors (e.g., green for eco-friendly models).

　　Materials:

　　Metal Casing: Made of galvanized steel plate or stainless steel, offering strong corrosion resistance and suitable for outdoor or coastal areas.

　　Non-metal Casing: Constructed from glass fiber reinforced plastic (GFRP), which is lightweight and has good insulation properties, commonly used in special scenarios (e.g., chemical plants).

　　3. Heat Dissipation Design

　　Heat Sinks: Aluminum or copper heat sinks with a sheet-like or corrugated shape are uniformly distributed on both sides or the top of the transformer, increasing the heat dissipation area.

　　Fans: Some models are equipped with forced air cooling systems, with fan covers made of metal mesh or plastic grilles to prevent foreign objects from entering.

　　II. Key Appearance Components

　　1. High-Voltage/Low-Voltage Windings

　　Winding Forms:

　　Epoxy Resin Casting: The surface is smooth and seamless, with uniform insulation layer thickness, and the color is mostly light gray or beige.

　　Vacuum Pressure Impregnation (VPI): Windings are wound with glass fiber tape and then impregnated with insulating varnish, resulting in a dark brown or black surface with a clear texture.

　　Labels: Voltage level labels (e.g., "10kV") are affixed to the ends of the windings, with some models also indicating phase sequences (A/B/C).

　　2. Iron Core

　　Material: The amorphous alloy iron core is stacked in thin strips, covered with insulating varnish, and has a color of dark gray or black.

　　Structure: The iron core is fixed to the windings through insulating supports, with the support color matching that of the windings to ensure compliance with electrical clearance standards.

　　3. Connection Terminals

　　High-Voltage Terminals: Made of copper or aluminum, with surfaces plated with tin or silver, shaped as cylindrical or conical, and equipped with insulating sleeves (mostly red or yellow).

　　Low-Voltage Terminals: Typically in a blade or fork shape, with the same surface treatment as high-voltage terminals, and insulating sleeves in blue or black.

　　Labels: Wiring diagrams or numbers (e.g., "U1/V1/W1") are marked beside the terminals for easy on-site wiring.

　　4. Protective Devices

　　Temperature Controller: Features an embedded digital display showing winding temperature, with some models equipped with alarm lights (red) and reset buttons.

　　Pressure Relief Valve: Located on the top of the transformer, cylindrical in shape, with a metal or plastic outer cover, and labeled "PRESSURE RELIEF".

　　Grounding Terminal: Clearly marked with the "⊥" symbol and using a yellow-green bicolored insulating sleeve to ensure reliable grounding.

　　III. Customized Appearance Options

　　1. Size and Shape

　　Compact Design: Reduces volume by optimizing winding layout and iron core structure, suitable for space-constrained locations (e.g., elevator machine rooms).

　　Irregular Casing: Custom L-shaped, U-shaped, or curved casings are designed based on installation positions to adapt to special architectural structures.

　　2. Color and Labels

　　Corporate Custom Colors: The outer casing is sprayed with corporate logos or standard colors to enhance brand image (e.g., green casings for data centers represent energy efficiency).

　　Warning Labels: "High Voltage Danger" signs are pasted in high-voltage areas, or safety operation guidelines are printed on the casing.

　　3. Additional Functional Modules

　　Smart Monitoring Interfaces: Reserved RS485 or Ethernet interfaces are provided for external sensors or communication modules, with corresponding openings in the casing and labeled interface types.

　　Lighting Devices: Built-in LED light strips are included for easy maintenance at night, with transparent or frosted plastic covers for the light strips.

　　IV. Correlation Between Appearance and Performance

　　Heat Dissipation Design Affects Capacity: Larger heat sink areas allow for higher transformer capacities (e.g., a 2000kVA transformer requires dual-fan forced air cooling).

　　Protection Rating Determines Application Scenarios: An IP54 casing prevents dust ingress and is suitable for textile mills; an IP65 casing is waterproof and suitable for outdoor landscape lighting.

　　Material Selection Affects Lifespan: Stainless steel casings can last over 20 years in coastal areas, while ordinary galvanized steel plates require regular anti-corrosion treatment.

　　V. Appearance Inspection Points

　　Factory Labels: Check if the nameplate is clear and includes information such as model, capacity, voltage, and manufacturing date.

　　Casing Integrity: Confirm that there are no deformations, cracks, or rust, and that the sealing strips are intact.

　　Connection Terminals: Check for looseness, oxidation, and whether the insulating sleeves are damaged.

　　Heat Dissipation Channels: Ensure that the heat sinks are not blocked and that the fans operate normally (if equipped).

　　Example Image Description:

　　A typical epoxy resin-cast dry-type transformer features a gray metal casing with dual fans on top and a temperature controller and pressure relief valve on the front; the windings are light gray, with high-voltage terminals having red insulating sleeves and low-voltage terminals having blue sleeves; the iron core is located behind the windings and covered with black insulating varnish.

　　By examining the appearance features, one can initially determine the type, performance, and applicable scenarios of a dry-type transformer. Actual procurement should be based on a comprehensive consideration of technical parameters and installation environment.