2CSG280395R1000 ABB CT1M-4 500 Current Transformer 500 A/5 A

Why Choose the ABB CT1M-4 500 Current Transformer?

The ABB CT1M-4 500, order code 2CSG280395R1000, is a 500 A/5 A through-primary current transformer designed for indirect measurement of electrical parameters in metering, monitoring and energy management applications. Part of ABB's Metering Accessories range, it transforms higher primary currents into a standardised 5 A secondary current for compatible electricity meters, ammeters, multimeters and network measuring instruments.

As part of the ABB CT1M current transformer series, the CT1M-4 500 is designed in accordance with IEC 61869-2 and uses a through-primary construction. The monitored cable or busbar passes through the transformer aperture, providing a practical current sensing solution for electrical distribution panels, switchboards and energy monitoring systems.

With a 500 A rated primary current, 5 A rated secondary current and accuracy class 0.5, the CT1M-4 500 provides a 500:5 transformation ratio for accurate indirect electrical measurement. It provides 5 VA at class 0.5, 7.5 VA at class 1 and 10 VA at class 3, while the CT1M-4 format accommodates cables up to 31 mm and horizontal busbars up to 40 × 10 mm or 30 × 20 mm.

Key Advantages

• Purpose-designed current transformer for indirect electrical measurement.
• 500 A/5 A current ratio for higher-current metering and monitoring applications.
• Accuracy class 0.5 supports precise current and energy measurement.
• 5 VA rated output at class 0.5 for accurate metering applications.
• Accommodates cables up to 31 mm and horizontal busbars up to 40 × 10 mm or 30 × 20 mm.
• FS 5 overcurrent limiting factor for metering applications.
• Optional DIN rail adapter provides additional installation flexibility.

Key Features

• ABB CT1M-4 current transformer series.
• 500 A rated primary current.
• 5 A rated secondary current.
• 500:5 current transformation ratio.
• Accuracy class 0.5.
• 5 VA rated output at class 0.5.
• 7.5 VA rated output at class 1.
• 10 VA rated output at class 3.
• 50–60 Hz rated frequency.
• IP20 protection rating.
• FS 5 overcurrent limiting factor.
• Through-primary construction for cable and busbar installations.

Reliable Indirect Measurement for Electrical Systems

Current transformers allow meters and measuring instruments to monitor electrical circuits carrying currents above their direct measurement range. The transformer produces a proportional secondary current, allowing electrical parameters to be measured without routing the full primary circuit current through the connected measuring instrument.

The ABB CT1M-4 500 converts a nominal 500 A primary current into a 5 A secondary current. Its class 0.5 accuracy, generous conductor aperture and through-primary construction make it suitable for integrating accurate indirect current measurement into commercial and industrial electrical distribution, power monitoring and energy management systems.

Typical Applications

• Electrical energy metering systems.
• Commercial and industrial distribution panels.
• Electrical switchboards and control cabinets.
• Indirect measurement of circuits with a 500 A nominal current.
• Energy monitoring and management systems.
• Current measurement with compatible ammeters, multimeters and energy meters.
• Cable and busbar current measurement.
• Panel-building and electrical instrumentation applications.