Structure and Meaning of Transformer Model Symbols

Dry-type transformer Symbols models typically consist of a combination of letters and numbers, each representing specific technical characteristics. Below is an example and breakdown:

• SCB10-1000KVA/10KV/0.4KV:
  • S: Three-phase transformer (D indicates single-phase).
  • C: Cast resin solid insulation.
  • B: Foil winding (R represents wire winding; L indicates aluminum winding).
  • 10: Design sequence number, where higher numbers denote newer technology.
  • 1000KVA: Rated capacity.
  • 10KV/0.4KV: Primary and secondary rated voltage.

Other letter arrangement order and meaning of Dry-Type Transformer Symbols

(1) Winding coupling method: ** (not marked); self-coupling (indicated by O).

(2) Number of phases: single phase (D); three phase (S).

(3) Winding external insulation medium: transformer oil (not marked); air (G); gas (Q); molded solid casting type (C); wrapping type (CR); flame retardant liquid (R).

(4) Type of cooling device: natural circulation cooling device (not marked); air cooler (F); water cooler (S).

(5) Oil circulation method: natural circulation (not marked); forced oil circulation (P).

(6) Number of windings: double winding (not marked); triple winding (S); double split winding (F).

(7) Voltage regulation method: no-excitation voltage regulation (not marked); on-load voltage regulation (Z).

(8) Coil conductor material: copper (not specified); copper foil (B); aluminum (L); aluminum foil (LB).

(9) Core material: electrical steel sheet (not specified); amorphous alloy (H).

(10) Special purpose or special structure: sealed (M); series connection (C); starting (Q); lightning protection (B); capacity adjustment (T); high impedance (K); ground station traction (QY); low noise (Z); cable lead-out (L); isolation (G); capacitor compensation (RB); oil field power lighting (Y); plant transformer (CY); fully insulated (J); synchronous motor excitation (LC).

Technical Features Behind the Symbols

• Insulation Type:
  • Cast resin type (C): Excellent fire resistance, suitable for indoor use.
  • Non-encapsulated type (G): High-temperature tolerance, ideal for industrial environments.
• Cooling Methods:
  • Natural cooling (AN): No additional equipment required, suitable for general applications.
  • Forced air cooling (AF): Uses fans for heat dissipation, ideal for high-load conditions.
• Winding Material:
  • Copper winding (no specific symbol): Superior conductivity, lower losses.
  • Aluminum winding (L): Cost-effective but slightly higher losses.

Connection Method Dry-Type Transformer Symbols Explanation

The connection method of dry-type transformers is often represented by codes like “Dyn11.” Below is a breakdown of common symbols:

Quick Guide to Nameplate Information

The nameplate on a dry-type transformer contains essential parameters that help buyers understand its performance:

• Rated Capacity: For example, “1000KVA” indicates the maximum load capacity.
• Primary/Secondary Voltage: For example, “10KV/0.4KV,” which specifies input and output voltage ranges.
• Frequency: Typically “50Hz” or “60Hz.”
• Insulation Class: For example, “F-class” or “H-class,” indicating heat resistance levels.

Application Scenarios and Selection Tips

Choose the right product based on symbols:

• For high-rise buildings, hospitals, or other locations requiring high safety standards, opt for SCB series cast resin transformers.
• For industrial equipment or high-load environments, select models with AF cooling methods for enhanced performance.