ABB 1TNA900241R0080 Current Transformer KORC 4SL 80/4

ABB 1TNA900241R0080 Current Transformer KORC 4SL 80/4

This is an ABB KORC Series, Ring-Type Current Transformer (CT). Its primary function is to safely and accurately measure high alternating currents (AC) in a power system and reduce them to a standardized, lower value that can be easily handled by measuring instruments like ammeters, energy meters, or protective relays.

Part Number Breakdown: ABB 1TNA900241R0080

This is ABB's internal manufacturing and catalog number. While the exact meaning of each segment is proprietary, we can infer its structure:

• 1TNA: Likely indicates the product family or series (in this case, the KORC series of current transformers).

• 900241: A unique identifier for this specific model and its attributes.

• R0080: Often references a specific characteristic, in this case, probably related to the 80/4 ratio.

Key Specifications from "KORC 4SL 80/4"

This part of the description holds the most critical technical data.

1. KORC

This is the model series. ABB's KORC series is a well-known range of ring-type (or window-type) current transformers designed for easy installation. They don't have a primary winding; instead, the main conductor (the cable or busbar carrying the current to be measured) is simply passed through the central "window."

2. 4SL

This indicates the accuracy class.

• '4' means the transformer has a 0.5% accuracy class at the rated current. This is a very high degree of accuracy, typically used for revenue metering and precision measurements where billing or high-fidelity data is involved.

• 'S' and 'L' are likely internal ABB codes specifying the design, construction, and possibly the burden (the load impedance the CT can drive while maintaining its accuracy).

3. 80/4

This is the most crucial specification: the Transformation Ratio.

• 80: The Primary Current (Ipn). This CT is designed for a nominal primary current of 80 Amperes.

• 4: The Secondary Current (Isn). When 80A flows through the primary conductor, the CT will output a standardized 4 Amperes.

This 80/4 ratio means the current is stepped down by a factor of 20 (80A / 4A = 20). So, if you measure 2 Amps on the secondary side, you know the actual current in the primary conductor is 2A * 20 = 40 Amperes.

• Manufacturer: ABB

• Type: Ring/Window Type Current Transformer (CT)

• Rated Primary Current (Ipn): 80 A

• Rated Secondary Current (Isn): 4 A

• Transformation Ratio: 80/4 (or 20:1)

• Accuracy Class: 0.5 (Class 0.5), suitable for precise measurement and billing.

• Installation: The main power cable is passed through the central hole.