China Y Series Current Transformer - Reliable Suppliers & Factory for Power Monitoring and Protection Solutions
Product Overview
A CT is driven by electromagnetic induction and is made composed of a secondary winding (many turns, attached to safety or measurement devices) and a main winding (few turns, connected in series with the high-current circuit). While the secondary winding, which is usually standardized to 5A or 1A for most industrial uses, receives a relatively modest current, the primary winding receives a significant current. This proportionality, also known as the transformation ratio, guarantees precise current measurement without subjecting workers or equipment to potentially hazardous voltages.
Important: The secondary winding should never be open-circuited while using a CT. An open circuit can generate extremely high voltages, which can seriously harm electronics and pose safety risks.
To summarize, current transformers are critical to ensuring the dependability, efficacy, and safety of modern electrical systems because they provide accurate current monitoring and enhanced fault protection.
High Precision
Essential for accurate energy metering in industrial applications.
Robust Linearity
Minimizes measurement distortion across the operating range.
Insulation Strength
Maintains high voltage isolation between primary and secondary windings.
Technical Parameters
| Type | Main Loop Current | (mm) Outline Size | |||||
|---|---|---|---|---|---|---|---|
| Y-25 | <63A | 25 | 55 | 60 | 45 | ||
| Y-45 | <100A | 45 | 79 | 84 | 24 | 66 | |
| Y-65 | <250A | 65 | 100 | 104 | 24 | 86 | |
| Y-80 | 80 | 119 | 26 | 101 | |||
| Y-100 | <630A | 100 | 136 | 141 | 26 | 114 | Ø5×14 |
| Y-150 | ≤1000A | 150 | 189 | 196 | 27 | 171 | Ø5×14 |
| Rated Primary Current: 1A | Rated Secondary Current: 0.5mA | ||||||
* All outline dimensions are in millimeters (mm).
Frequently Asked Questions (FAQ)
❓ What is a Current Transformer (CT) and how does it work?
A Current Transformer (CT) operates on the principle of electromagnetic induction. It consists of a primary winding connected in series with the high-current circuit and a secondary winding connected to measurement or protection devices. The CT steps down the high primary current to a standardized lower value (typically 1A or 5A), allowing safe and accurate measurement without direct contact with the high-current line.
❓ Why should the secondary winding of a CT never be left open-circuited?
If the secondary winding of a CT is open-circuited while the primary is energized, the magnetic flux in the core is no longer balanced by a secondary current. This causes the core to saturate and generates dangerously high voltages across the secondary terminals, which can damage the insulation, destroy connected equipment, and pose a serious safety hazard to personnel.
❓ What are the key performance requirements for a current transformer?
The three most critical performance requirements for a CT are: High Precision — necessary for accurate energy metering and billing; Robust Linearity — ensures measurement accuracy across a wide range of currents without distortion; and Insulation Strength — maintains safe electrical isolation between the high-voltage primary and the low-voltage secondary circuits.
❓ What current ratings are available in the Y-series CT models?
The Y-series current transformers cover a wide range of primary current ratings to suit various industrial applications: Y-25 supports up to 63A, Y-45 up to 100A, Y-65 up to 250A, Y-100 up to 630A, and Y-150 up to 1000A. The rated secondary current for all models is 0.5mA with a rated primary current of 1A.
❓ How do I select the right CT model for my application?
Selecting the correct CT model depends primarily on the maximum primary current in your circuit. Choose a model whose rated primary current is equal to or greater than the maximum expected load current. Additionally, consider the physical outline dimensions to ensure the CT fits within your installation space, and verify that the transformation ratio meets the accuracy requirements of your metering or protection system.
❓ What industries and applications commonly use these current transformers?
Current transformers of this type are widely used across power distribution systems, industrial automation, energy management, smart metering, motor protection, and electrical panel manufacturing. They are essential wherever accurate current monitoring, energy measurement, or overcurrent protection is required in medium-to-high current electrical circuits.