One transformer for round conductor and busbar Plug-on current transformer with 28 mm round opening and primary bars up to 30 × 15 mm Primary currents from 50 A to 750 A Secondary 1 A or 5 A, contact protection as standard Round conductor Ø 28 mm or busbar up to 30 × 15 mm Ideal for: switchgear, power distribution, retrofit installations The series with integrated short-circuit bridge Compact current transformers for DIN rail – safe and easy to install Integrated short-circuit bridge as standard Primary currents from 50/5 A to 4000/5 A Split-core current transformer with integrated short-circuit bridge Quick retrofit on existing busbars and cables – without power interruption Easy installation with hinged housing design Integrated short-circuit bridge for safe transformer replacement Primary currents from 100/5 A to 3000/5 A Accuracy class 0.5 – suitable for billing purposes Ideal for: Switchgear retrofit, utilities, industrial plants Flexible current measurement for high currents – without iron core Lighter, more compact and flexible than conventional current transformers Linear measuring range without saturation effects Flexible and lightweight – ideal for confined spaces Measuring range up to 10,000 A and beyond Open design for easy retrofit installation Ideal for: High-current applications, energy monitoring, switchgear CEL-NA-S Grid Protection Relay Grid and system protection relay acc. to VDE-AR-N 4105/4110/4120 Standard-compliant monitoring of voltage, frequency, ROCOF/vector shift and phase sequence 3 potential-free changeover relays for coupler switch control Digital inputs for feedback and remote disconnection Optional Modbus RTU interface for extended communication Voltage range 3×100–690 V AC, 50/60 Hz Applications: PV systems, CHP, storage, wind and hydropower Compact current transformer series with short-circuit bridge Space-saving on DIN rail – class 0.5 and 1 for metering and protection Compact design for space-saving DIN rail mounting Various sizes for every requirement Ideal for: Switchgear, power distribution, industrial plants Why CELSA measuring devices? Current transformers made in Germany Broad range of measuring technology and grid protection Practical, application-oriented consultation Energieversorger & Stadtwerke FAQ about Current Transformers We manufacture busbar current transformers, wound-primary transformers, split-core transformers as well as summation and protection transformers. Key factors are the transformation ratio, the required burden (power in VA), and the accuracy class (e.g., class 0.5 or 0.2s). Our current transformers are manufactured in Germany. This ensures high production quality, short delivery routes and close quality control.