The capacity of an SCB10 dry-type transformer directly dictates its ability to power your electrical equipment—too small, and it risks overload; too large, and it wastes energy and capital. To determine the right capacity, you’ll need to analyze three key factors:
- The active power (kW) of all connected devices (sum of the actual power consumed by motors, machinery, lighting, and other loads).
- The power factor (cosφ) of your system (typically 0.8–0.9 for industrial and commercial applications; lower values indicate inefficient power use).
- The load factor (a safety margin to accommodate future expansion or peak demand, usually 1.1–1.2 times the calculated load).
A general formula for capacity calculation is:
Transformer Capacity (kVA) = (Total Active Power × Load Factor) / Power Factor
For example, if your total active power is 800kW, power factor is 0.85, and load factor is 1.15, the required capacity would be (800 × 1.15) / 0.85 ≈ 1082kVA—meaning a 1250kVA SCB10 transformer would be the optimal choice to avoid under-sizing.
Rated voltage refers to the maximum safe operating voltage for the transformer’s primary (input) and secondary (output) windings. It’s defined by the voltage ratio—the fixed proportion between primary and secondary voltages—which directly impacts compatibility with your power grid and equipment.
Common voltage ratios for SCB10 transformers include:
- 10kV/0.4kV: The most widely used ratio for residential communities, commercial buildings, and small-to-medium industrial facilities (matches China’s standard low-voltage supply of 380V/220V).
- 10kV/0.6kV: Designed for specialized industrial equipment (e.g., certain motors or control systems) that require a 600V power supply.
Voltage ratio also influences the transformer’s price: ratios for non-standard grids (e.g., 20kV/0.4kV) may require customized winding designs, increasing material and manufacturing costs. Always confirm your grid’s incoming voltage and your equipment’s rated voltage before selecting a ratio.
Fluctuations in grid voltage (common during peak demand or line faults) can damage sensitive equipment—making the transformer’s voltage regulation capability a key parameter. SCB10 transformers offer two regulation methods, each suited to different scenarios:
- How it works: Adjustments are made only when the transformer is de-energized (power cut off). Tap changers on the primary winding modify the number of coil turns to correct voltage.
- Pros: Cost-effective, simple design, high reliability.
- Cons: Requires downtime for adjustments—ideal for stable loads (e.g., residential areas with consistent power use).
- How it works: Adjustments are performed while the transformer is live (under load), using a specialized tap changer that switches between turns without interrupting power.
- Pros: No downtime, real-time voltage correction, suitable for fluctuating grids or critical loads (e.g., data centers, hospitals, industrial production lines).
- Cons: Higher cost and complex maintenance compared to non-excitation regulation.
When selecting, prioritize on-load regulation if your operation cannot tolerate power outages; otherwise, non-excitation regulation offers a cost-efficient solution.
Connection groups define the wiring method of the transformer’s primary and secondary windings, as well as the phase relationship between input and output voltages. The two most common types for SCB10 transformers are Dyn11 and Yyn0, with distinct advantages:
- Wiring: Primary winding (high-voltage) uses delta (D) connection; secondary winding (low-voltage) uses star (y) connection with a neutral point (n); phase shift of 11 o’clock (30° lag).
- Key Benefit: The delta primary winding effectively absorbs third-order and other high-order harmonics (generated by non-linear loads like inverters or LED lighting), preventing harmonic pollution of the power grid. This is the dominant connection method in China due to its superior harmonic suppression.
- Compatibility: Works with both neutral-point direct grounding and indirect grounding systems.
- Wiring: Both primary and secondary windings use star (Y/y) connection with a neutral point (n); no phase shift (0 o’clock).
- Key Benefit: Simple structure, lower cost, and suitable for balanced loads (e.g., pure resistive heating equipment).
- Limitations: Poor harmonic suppression; only compatible with neutral-point direct grounding systems (common in residential grids).
For most commercial and industrial applications, Dyn11 is preferred for its versatility and ability to protect both your equipment and the grid from harmonic damage.
Early consideration of transformer dimensions is critical to avoid installation delays or safety hazards. While SCB10 transformers comply with national and international standards (e.g., IEC 60076, GB/T 1094), you must also align with your on-site conditions:
- Key measurements to confirm: Overall width, height, depth, and base dimensions (ensure compatibility with your foundation or mounting platform).
- Ventilation space: Dry-type transformers rely on air cooling—reserve a minimum of 800mm clearance from walls and 300mm between adjacent transformers to ensure adequate heat dissipation.
- Site constraints: For tight spaces (e.g., basement substations or compact industrial facilities), consult the manufacturer for customized low-profile or narrow-width models.
Always share your installation site’s dimensions and ventilation capacity with the supplier to confirm a perfect fit.
SCB10 dry-type transformers require protective enclosures to shield internal components from dust, moisture, and physical damage. The choice of material impacts durability, maintenance needs, and cost:
- Features: Cost-effective, lightweight, and easy to process. Typically coated with anti-corrosion paint for indoor use.
- Best For: Dry, clean indoor environments (e.g., commercial building substations, office complexes).
- Features: High corrosion resistance, rust-proof, and durable. Withstands humidity, dust, and mild chemical exposure.
- Best For: Outdoor installations, coastal areas (saline air), or industrial environments with moisture or corrosive fumes.
- Features: Lightweight, excellent heat dissipation, and corrosion-resistant. Ideal for space-constrained or weight-sensitive locations.
- Best For: High-rise buildings, rooftop substations, or areas where easy transportation and installation are priorities.
Enclosure material directly affects the transformer’s lifespan and maintenance frequency—invest in stainless steel or aluminum alloy if your site has harsh environmental conditions, even if it increases upfront costs.
By focusing on these six core parameters, you can select an SCB10 dry-type transformer that aligns with your power needs, budget, and installation constraints. For customized solutions or further technical guidance, consult with your transformer supplier to ensure optimal performance and long-term reliability.
