2CSG280755R1000 ABB CT1M-S-30 400 Current Transformer 400 A/5 A

Why Choose the ABB CT1M-S-30 400 Current Transformer?

The ABB CT1M-S-30 400, order code 2CSG280755R1000, is a 400 A/5 A split-core 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 a nominal 400 A primary current into a standardised 5 A secondary current for compatible electricity meters, network analysers and measuring instruments.

The ABB CT1M-S series is designed for applications where a split-core current transformer can simplify installation around an existing conductor or busbar. The CT1M-S-30 range covers primary currents from 100 A to 400 A, with the 400 A model providing the series' class 0.5 measurement accuracy and a compact through-primary format suitable for electrical distribution and energy monitoring systems.

With a 400 A rated primary current, 5 A rated secondary current and accuracy class 0.5, the CT1M-S-30 400 provides a 400:5 transformation ratio for accurate indirect electrical measurement. It delivers 3.75 VA at class 0.5, 6.25 VA at class 1 and 10 VA at class 3, with a CT1M-S-30 series through-primary opening designed for vertical busbars up to 33 × 23 mm.

Key Advantages

• Split-core construction supports convenient installation in existing electrical systems.
• 400 A/5 A current ratio for compatible metering and monitoring equipment.
• Accuracy class 0.5 supports precise current and energy measurement.
• 3.75 VA rated output at class 0.5.
• CT1M-S-30 series aperture accommodates vertical busbars up to 33 × 23 mm.
• IP20 protection for installation within suitable electrical enclosures.
• Designed for indirect measurement without passing the full primary current through the connected measuring instrument.

Key Features

• ABB CT1M-S-30 current transformer series.
• Split-core through-primary design.
• 400 A rated primary current.
• 5 A rated secondary current.
• 400:5 current transformation ratio.
• Accuracy class 0.5.
• 3.75 VA rated output at class 0.5.
• 6.25 VA rated output at class 1.
• 10 VA rated output at class 3.
• 50–60 Hz rated frequency.
• IP20 protection rating.
• 720 V maximum operating voltage.
• 120% continuous overload capability.
• 4 kV at 50 Hz for 1 minute test voltage.

Practical Split-Core Measurement for Existing Electrical Installations

Current transformers allow meters and measuring instruments to monitor electrical circuits carrying currents above their direct measurement range. A proportional secondary current is supplied to the measuring device, allowing electrical parameters to be monitored without routing the full primary circuit current through the meter or analyser.

The ABB CT1M-S-30 400 combines this measurement principle with a split-core design, making it particularly useful for maintenance, upgrades and extensions to existing distribution systems. Its 400 A/5 A ratio, class 0.5 accuracy and compact CT1M-S-30 format provide a practical solution for energy metering and current monitoring where installation around an existing busbar is desirable.

Typical Applications

• Electrical energy metering systems.
• Commercial and industrial power distribution installations.
• Distribution panel switchboards and power centres.
• Indirect measurement of circuits with a 400 A nominal current.
• Energy monitoring and management systems.
• Current measurement with compatible network analysers, meters and instrumentation.
• Retrofit metering and monitoring installations.
• Maintenance and extension of existing electrical distribution systems.