The Circutor TQ-6 (code M74028) is a single-phase split core current transformer with a 300/5 A transformation ratio, designed for live-circuit installation on flat conductors and busbars up to 20 30 mm. Its button-opening core clips onto existing conductors without the need to disconnect power, making it well suited to retrofit metering work. Three accuracy classes – 0.5, 1, and 3 – are supported with corresponding burdens of 0.5 VA, 1 VA, and 2 VA.

Technical specifications:

• Model: TQ-6
• Circutor code: M74028
• EAN: 8433059299859
• Transformer type: Split core, button opening
• System: Single-phase
• Transformation ratio: 300/5 A
• Primary current: 300 A
• Maximum flat strip / busbar: 20 30 mm
• Class 0.5 burden: 0.5 VA
• Class 1 burden: 1 VA
• Class 3 burden: 2 VA
• Safety factor (SF): 10
• Insulation voltage (S1-S2): 3 kV
• Operating voltage: 0.72 kV AC max
• Nominal frequency: 50/60 Hz
• Thermal short-circuit current (Ith): 60 In
• Dynamic current (Idyn): 2.5 Ith
• Protection class: IP 20
• Enclosure: Self-extinguishing plastic, UL 94 V0
• Thermal class: B (130 C)
• Working temperature: -5 to +40 C
• Storage temperature: -40 to +85 C
• Relative humidity: 15 to 85% (non-condensing)
• Maximum installation altitude: 1000 m
• Dimensions (W H D): 80 98.5 28 mm
• Weight: 0.254 kg
• Mounting: Wall mount or DIN rail (accessory required)
• Standards: UNE-EN 61869-1, UNE-EN 61869-2, UNE 21031, UL 94

Features and benefits:

• Button-opening split core allows installation on live conductors without interrupting supply or disconnecting load
• Accepts flat busbars up to 20 30 mm, covering typical LV panel busbar cross-sections
• Three accuracy classes – 0.5, 1, and 3 – in a single unit cover revenue metering, general energy monitoring, and less demanding measurement applications
• V0 self-extinguishing plastic housing reduces fire-propagation risk inside switchgear enclosures
• Optional DIN rail mounting accessory allows standard panel fitment alongside other din-rail devices

Applications:

• Retrofit energy sub-metering on live low-voltage distribution boards
• Current sensing for energy monitors and power analysers in industrial panels
• Single-phase power measurement in building energy management and smart-meter installations
• Instrumentation on flat busbar sections where panel shutdown is not permitted

Also known as: Circutor TQ-6, TQ-6 M74028, TQ6 300/5A, split core current transformer 300/5A, 20×30 busbar current transformer.