ABB ESM2000-7041 Current Transformer 

1. Key Parameters

• Product Model: ESM2000-7041 (standard identifier for ABB’s ESM2000 series current transformers)
• Product Series: ESM2000 series (ABB’s compact, low-loss current transformers for LV/MV systems)
• Core Function: Steps down high primary AC currents to low, standardized secondary currents for measurement, protection, and control
• Current Ratings:
  • Primary Rated Current (Iₚₙ): 700A (continuous operating current)
  • Secondary Rated Current (Iₛₙ): 5A (standard output; 1A optional via custom configuration)
  • Accuracy Class (Measurement): 0.5 (for precise energy metering and current monitoring, error ≤±0.5% at rated current)
  • Accuracy Class (Protection): 5P20 (for overcurrent/short-circuit protection, error ≤±5% at 20× rated primary current)
• Electrical Ratings:
  • Rated Voltage (Uₙ): Up to 12kV AC (insulation voltage for MV applications; 690V AC for LV variants)
  • Frequency Range: 50/60Hz (compatible with global power systems)
  • Short-Time Thermal Current (Iₜₕ): 31.5kA (1-second duration; withstands thermal stress during short-circuits)
  • Short-Circuit Dynamic Current (I_dyn): 78kA (withstands mechanical stress from short-circuit current peaks)
• Mechanical Specifications:
  • Type: Window-type (split-core optional for retrofitting without power shutdown)
  • Window Size (W×H): 41mm × 41mm (accommodates primary conductors up to 35mm² copper)
  • Dimensions (Overall W×H×D): 120mm × 150mm × 80mm (compact design for switchgear integration)
  • Weight: Approximately 1.8kg
  • Mounting: DIN rail mounting (35mm standard) or panel mounting (via threaded studs)
• Insulation & Protection:
  • Insulation Class: Class 155 (polyester film insulation, withstands 155℃ continuous operating temperature)
  • Protection Class: IP20 (when installed in switchgear; IP40 optional for exposed installations)
  • Dielectric Strength: 30kV AC (1-minute withstand voltage between primary and secondary windings)
• Compliance Standards: IEC 61869-2 (current transformers for measurement and protection), EN 61869-2, ANSI C57.13 (for North American markets)

2. Product Features

• Dual Accuracy Classes: Combines 0.5 class (measurement) and 5P20 class (protection) in one unit—eliminates the need for separate CTs for metering and protection, reducing system cost and installation space.
• High Short-Circuit Withstand Capacity: 31.5kA short-time thermal current and 78kA dynamic current ratings ensure durability during severe short-circuit events (e.g., in industrial power distribution systems), preventing insulation breakdown or mechanical damage.
• Compact Window Design: 41mm×41mm window accommodates common primary conductor sizes (up to 35mm² copper), while the overall compact profile fits into high-density switchgear or control panels—ideal for space-constrained applications.
• Flexible Mounting Options: Supports both DIN rail and panel mounting, adapting to diverse switchgear layouts (e.g., LV motor control centers, MV switchboards). Split-core variants enable retrofitting without disconnecting primary power, minimizing downtime.
• Low Power Loss: Optimized core design (high-grade silicon steel) reduces no-load losses (<0.5VA at rated voltage) and load losses (<3VA at rated current), improving energy efficiency in metering systems and reducing heat generation.
• Wide Voltage Compatibility: Rated for up to 12kV AC, making it suitable for both MV (e.g., 10kV distribution) and LV (e.g., 400V industrial) applications—eliminating the need for product variants across voltage tiers.
• Reliable Insulation: Class 155 insulation and 30kV AC dielectric strength ensure safe operation in high-temperature or high-voltage environments (e.g., power substations, industrial plants with voltage transients).

3. Application Fields

• Industrial Power Distribution: Installed in LV/MV switchgear for manufacturing plants (steel, cement, automotive) to measure and protect feeder circuits, motor loads, and transformers—ensuring accurate energy monitoring and fast fault response.
• Commercial Buildings: Used in office towers, shopping malls, and data centers to meter main incoming power and protect distribution panels from overcurrents—supporting energy management systems (EMS) and compliance with utility metering standards.
• Utility Substations: Deployed in 10kV/6kV MV distribution substations to feed current signals to protection relays (e.g., ABB RET615) and revenue meters—ensuring grid stability and accurate billing for end-users.
• Renewable Energy Systems: Integrated into solar farms and wind parks to measure inverter output currents and protect grid-connection circuits—complying with grid codes for current monitoring and fault ride-through.
• Critical Infrastructure: Used in hospitals, airports, and wastewater treatment plants to protect emergency power systems (e.g., backup generators, UPS) and ensure reliable current measurement for life-critical loads.
• Retrofit Projects: Split-core variants (optional) enable easy installation in existing power systems without shutting down primary power—ideal for upgrading old metering or protection systems in industrial facilities.

4. Precautions

• Current Rating Matching: Ensure the primary rated current (700A) aligns with the maximum expected current of the primary circuit—over-sizing (e.g., using a 700A CT for a 300A circuit) reduces measurement accuracy, while under-sizing risks overheating.
• Secondary Circuit Safety: Never open the secondary circuit of a CT during operation—open-circuited secondaries generate extremely high voltages (up to several kV), which can damage insulation or cause electric shock. Always short-circuit the secondary terminals before disconnecting meters/relays.
• Conductor Sizing: Use appropriately sized secondary cables (minimum 2.5mm² copper) to minimize voltage drop—voltage drop >0.1V at rated secondary current (5A) will degrade protection relay accuracy.
• Insulation Compatibility: For MV applications (≥1kV), confirm the CT’s rated voltage (12kV) matches the system voltage—using a LV CT (690V) in an MV circuit will cause dielectric breakdown.
• Mounting & Installation: Ensure the primary conductor is centered in the CT window to avoid “off-center error” (measurement deviation >1%). For split-core CTs, ensure the core is fully closed and latched to maintain accuracy.
• Environmental Limits: Operate within the -25℃~+70℃ temperature range; avoid exposure to corrosive gases (e.g., sulfur, chlorine) or moisture (IP20 CTs require a sealed switchgear cabinet). Clean the CT surface periodically to remove dust buildup (avoids overheating)