Comewill, a trusted China-based manufacturer and supplier of electrical equipment, offers high-quality Combined Instrument Transformers that integrate Current Transformer and Voltage Transformer functions in a single unit. Available in stock, wholesale, and customized, these transformers provide compact, safe, and cost-effective solutions for electrical energy measurement and protection in distribution systems. They are widely used in industrial, mining, and rural power grid applications.
Combined Instrument Transformers are kind of electrical device that merges current and voltage transformer functions into one enclosure. The current unit is connected in series to the high-current line, while the voltage unit is connected in parallel to the high-voltage line. Both units share a common core and insulation, enabling simultaneous acquisition of voltage and current signals while isolating high-voltage primary circuits from secondary measuring devices. This design ensures operator and equipment safety while reducing installation complexity.
Voltage Measurement
The voltage section induces a proportional low voltage in the secondary winding when high voltage flows through the primary circuit. This low-voltage output (typically 100V) is then used by voltmeters, energy meters, or protective relays.
Current Measurement
The current section converts large primary currents into small, measurable secondary currents (usually 5A or 1A). These outputs are supplied to Current Transformer meters or relay protection devices, maintaining accurate monitoring and measurement.
Isolation and Safety
Inside a combined transformer, current and voltage units are encapsulated in a shared insulation shell, often oil-filled or epoxy-cast. The secondary side must be grounded, and circuits must avoid open or short conditions to ensure safety.
Comewill factory's Combined Instrument Transformers are suitable for:
High-voltage metering boxes
Column-mounted transformers
Distribution cabinets
They are particularly useful in three-phase measurement scenarios, such as V/V (two voltage transformers) or Y/Y (three voltage transformers) configurations for balanced or unbalanced loads.
1. Compact Design and Easy Installation – Integrating current and voltage transformers into one unit reduces footprint and simplifies setup.
2. Cost Efficiency – Purchasing a combined unit reduces separate transformer costs, manufacturing complexity, and installation time.
3. Electrical Isolation and Reliability – Complete separation of high-voltage primary and low-voltage secondary circuits ensures operator and equipment safety.
4. Integrated Measurement and Protection – Provides standard outputs for energy meters and relay protection devices simultaneously.
5. Environmental Adaptability – Oil-immersed or gas-insulated designs allow long-term operation outdoors or in harsh conditions.
Combination Transformer – Combines current and voltage transformers into one device for compact installation and synchronized measurement. Suitable for space-limited or cost-sensitive projects.
Split Transformer – Separates current and voltage transformers for flexible placement and optimized accuracy. Allows customized selection for different voltage and current levels.
Comewill, as a China-based factory and supplier, provides quality, low-price, and customized combined instrument transformers that are in stock for fast delivery. Our Current Transformer systems are manufactured under strict quality standards to meet industrial and utility requirements, ensuring accurate measurement, operational safety, and reliable long-term use.
