REDARTI RED-KTL Series Thyristor-Controlled Cataphoresis (KTL) Rectifiers are heavy-duty power systems designed to provide the high voltage stability and precise current regulation required by anodic/cathodic electrophoretic dip-coating baths in automotive OEM and supplier, white-goods, machinery, mould and industrial metal-coating plants. They guarantee that the micron thickness (15–40 µm) that gives metal surfaces the highest level of corrosion resistance is distributed homogeneously across the plant.
They are built with 3 flexible cooling architectures — air-cooled (A), water-cooled (W) or oil-cooled (O) — tailored to the customer and plant infrastructure. Our standard production range covers 150V - 800V DC output voltage and 50 A - 3,000 A DC output current, and we also build tailor-made high-power / special-parameter units to suit specific processes and tank capacities.
Depending on operating needs, they can be built with 6-pulse (300 Hz) or 12-pulse (600 Hz, low-ripple) thyristor rectifier modules. In addition to manual or full-automation (PLC & SCADA) compatible control, digital LCD panel or Siemens PLC-based colour touchscreen (HMI) configurations are available.
6-Pulse and 12-Pulse Thyristor Technology & Its Importance in the Cataphoresis Process
In cataphoresis (KTL) baths, the electric field distribution and DC quality directly determine how smooth and pore-free the coating film is:
- 6-Pulse (300 Hz) Thyristor Rectifier Technology: A highly efficient, economical rectification solution for standard industrial cataphoresis applications. With a 300 Hz ripple frequency, it delivers ideal surface quality and strong corrosion protection in general automotive-supplier and metal-component coating baths.
- 12-Pulse (600 Hz Low-Ripple) Thyristor Technology: Designed for top-level automotive OEM specifications and KTL coating lines requiring high precision. Thanks to a special phase-shifting transformer design, the output ripple factor falls below 3%. Low ripple stabilises the electric field in the bath, delivering smooth film quality even on the internal holes and recessed surfaces of complex parts, and minimises the harmonics drawn from the grid.
Key Features
- Wide Voltage and Current Range (150V - 800V DC / 50 A - 3,000 A DC): Full-range regulation with high voltage from 150V to 800V and current capacity from 50 A to 3,000 A (power built to plant requirements).
- Flexible Cooling Architecture: Heavy-duty air-cooled (A), water-cooled (W) or oil-cooled (O) versions that fully adapt to harsh factory and ambient conditions.
- 6-Pulse / 12-Pulse Rectification Option: A modular thyristor group in 6-pulse (300 Hz) or ultra-low-ripple 12-pulse (600 Hz) according to the plant's process standard.
- Flexible Display & Control Option: A control panel with digital LCD or a 10-inch Siemens PLC-based colour touchscreen (HMI).
- Fully Automation-Compatible Communication: 100% integration into factory automation (SCADA) via Profinet, Modbus RTU (RS485) and Ethernet interfaces.
- Ramped and Stepped KTL Operating Program: A soft-start and stepped ramp profile that raises current and voltage without jumps and without damaging the parts.
- Industrial Safety & Dual-Side Safety Interlocks: Cover-open warning/stop on both the bath side and the rectifier side, emergency-stop warning, phase missing/reversed/low/high, and over-temperature/over-current protection.
Applications
- Automotive OEM and Supplier Cataphoresis Lines: KTL dip-coating processes for vehicle chassis, body parts, suspension and sheet-metal components.
- White Goods and Metalware Manufacturing: Corrosion-protective priming of washing machine/dishwasher housings, radiators and metal furniture parts.
- Heavy-Duty Commercial Vehicle and Construction Machinery Parts: High-voltage dip coating of construction machinery, agricultural equipment and truck chassis.
- Job-Shop Cataphoresis Coating Plants: Series cataphoresis lines with varying part geometries and recipe-based production.
