ABB 1TNA900141R0110 Current Transformer KORC 4L 110/4

ABB 1TNA900141R0110 is a dual-winding current transformer suitable for 12kV medium-voltage systems with a ratio of 110/4. It provides a 0.5-class measuring winding for high-precision metering and a 5P10-class protection winding for fault detection, making it a reliable and widely used standard product in power systems.

Product Overview

• Brand: ABB

• Full Model: 1TNA900141R0110

• Product Series: KORC 4L

• Type: Window-type / Through-type Current Transformer

• Primary Purpose: Installed in metal-enclosed medium-voltage switchgear (e.g., ABB UniGear) for system current measurement and electrical protection.

• Key Features: Compact structure, high accuracy, strong reliability, and a common standard component in ABB medium-voltage switchgear.

Detailed Technical Parameters

Based on the model code and series characteristics, its main parameters are as follows:

Parameter Category

Parameter Item

Detailed Specification

Basic Information

Full Model

1TNA900141R0110

Product Series

KORC 4L

Description

Window-type Current Transformer

Primary Side Parameters

Rated Primary Current (Ipr)

110 A

Installation Method

Through-type (Cable or busbar passes through the center hole)

Secondary Side Parameters

Rated Secondary Current (Isr)

4 A

Output

2 independent cores and secondary windings (Dual-winding)

Core 1 (C1)

Accuracy Class

0.5

Rated Burden (Burden)

15 VA

Function

For precise measurement (Connecting to energy meters, ammeters, etc.)

Core 2 (C2)

Accuracy Class

5P

Rated Burden (Burden)

15 VA

Accuracy Limit Factor (ALF)

10

Accuracy Limit Current

10 x Ipr = 1100 A

Function

For relay protection (Connecting to protection relays)

General Parameters

Frequency

50/60 Hz

Rated Insulation Level

Suitable for 12kV systems (Common value, please refer to the official datasheet for confirmation)

Power Frequency Withstand Voltage

Typically 28 kV / 1 min

Impulse Withstand Voltage

Typically 60 kV

Standard

Complies with international standards such as IEC 61869-1, IEC 61869-2

Model Code Interpretation

• 1TNA900141R0110: ABB's unique material number.

• KORC 4L: Product series name.

◦ KORC is the series code.

◦ 4L indicates the design framework of the series, which may support up to 4 windings, but this specific model is configured with 2 windings.

• 110/4: This is the most crucial identification code.

◦ 110: Indicates the rated primary current is 110 Amps. This is the main difference from models ending with R0185 (primary current 185A).

◦ 4: Indicates the rated secondary current is 4 Amps.

Application and Selection Points

1. Current Matching: Ensure the CT's 110A primary rated current matches the normal operating current of your circuit. Selecting a rating that is too high reduces measurement accuracy; one that is too low can cause CT saturation or damage.

2. System Voltage: Confirm that its rated insulation level (e.g., 12kV) is suitable for your switchgear system.

3. Secondary Burden: The total impedance of all devices and wires connected to both the measuring winding (0.5 class) and the protection winding (5P10) must not exceed the rated burden of 15 VA, otherwise accuracy and performance will be affected.

4. Protection Capability: The protection winding (5P10) can ensure an error not exceeding 5% under fault currents up to 10 times the rated primary current (i.e., 1100A), guaranteeing reliable operation of the protection relay.

5. Safe Installation: Safety regulations must be followed; the CT secondary side must never be open-circuited at any time to prevent the generation of high voltages hazardous to personnel and equipment.