B 20K

Resistance Welding in Perfection

With the B 20K high-performance welding control system, you simply achieve better welding results.

The B 20K combines all process, measurement and monitoring systems into one comprehensive system. Stepless welding frequency adjustment between 1,000 and 20,000 Hz guarantees a highly dynamic and even finer control compared to low-frequency technologies for even better resistance welding results.

From micro to macro welding processes, from resistance soldering processes to heating processes such as annealing, the B 20K covers an immense range of applications. Furthermore, up to 18 servo axes for e.g. controlling contact welding equipment can also be used to integrate press applications and other options in the B 20K.


Stand-alone with touchscreen operation and keyboard on the control cabinet.

The standard version includes 2 welding positions. Extensions with a maximum of 8 welding positions are possible with additional cabinets. This version provides compatibility with the B 1000 and B 5000 welding control systems. Input and output functions are possible without programming. The variety of applications for the stand-alone version ranges from integration in production and manufacturing systems to replacing existing B 1000 and B 5000 welding control systems.

Stand-alone with NC control for welding tools.

Can be integrated in an existing machine or an existing production system. In doing so, the B 20K is extended with additional axis cabinets. Application for integrating welding tasks with progressive equipment under a press. This allows for the integration of welding tool movements independent of a fixed press stroke. Faster process times, no bounce behavior of the press head, reduced electrode wear and simplified integration compared to conventional practices can be achieved.

All-in-one version.

Can be integrated in an existing machine or an existing production system. The B 20K-VC 1 combines welding control, machine and process control with all features of the B 20K and the VC 1 VariControl. Functions of both control platforms can be linked and exchanged with two-way communication as well as merged to form a single control system. All elements required for welding, production and assembly tasks are integrated to enable implementing a fully automatic production solution.

70 to 220kVA

  • No modification
  • No replacement
  • Universal hardware base


Process Frequencies of Up to 20,000 Hz

  • Compared to low process frequencies, the higher process frequencies allow for even more adjustment options to apply the energy required for the welding process metered and targeted. This leads to higher quality and an extended range of welding applications.

100% Protection from Power Fluctuations

  • The standard active power supply module offers protection from power fluctuations. The active power supply module provides a separate supply voltage for the inverter independent of the mains voltage. This means the inverter supply is independent of mains voltage drops and fluctuations and maximum process reliability is guaranteed.

Maximum Process Transparency

  • Five standard measuring channels for logging welding process data are integrated in the B 20K. Measuring curves and measured values can be used for closed-loop control, process monitoring and diagnostic functions and provide all options required for a reliable and transparent welding process.

Quick Welding Profile Manipulation During Production

  • Automatically with a stepper function that changes the welding profile after a defined number of welds. Manually with the quick online parameter adjustment feature. In both cases, there is no machine downtime and the welding parameters can be identified, adapted and optimized quickly.

Contactless Heating by Induction Annealing

  • The B 20K provides compatibility to integrate an inductor (instead of the welding transformer). With an inductor, steels and non-ferrous metals can be heated contactless.

Control of NC Axes

  • In addition to the process, measuring and monitoring functions, servo-controlled movements for welding applications can be easily implemented in the B 20K. Motion sequences for the welding tool are now performed independently by the welding control system and can be integrated into all existing production systems.

From Micro to Macro Welding

All Resistance Welding Processes With One Single Welding Control System

  • Transformer Types 70 kVA, 130 kVA, 170 kVA, 220 kVA
  • Welding frequencies (Transformer Type) 10 kHz – 20 kHz (70 kVA), 1 kHz – 5 kHz (130 kVA, 170 kVA, 220 kVA)
  • Mains Voltage Range Three-Phase Current 230–480V for transformer with 70 and 130kVA 400–480V for transformer with 70, 130, 170 and 220kVA, 50/60Hz
  • Number of Welding Programs 25
  • Control Method Current profile control, output profile control, reference curve for current reference curve for output
  • Stepper Function for Open / Closed-Loop Control Modes No control, current profile control, output profile control
  • Measuring signal inputs (1) – (5) (1) Current, (2) voltage, (3) force, (4) distance, (5) additional measuring channel (-10 – +10V)
  • Supply Voltage U1 See above
  • Max. Output Smax 250kVA at 400V
  • Rated Power SN 33 Max. 230kVA at 50% ED / 400V dependent on transformer type
  • Welding Current Range I2 100–40,000A at 6% ED
  • Welding Voltage U2N 7–14VDC (dependent on transformer type)
  • Interfaces, Data Backup / Data Exchange ETHERNET, USB / OPC UA
  • Digital Inputs / Outputs 24VDC, rotary encoder (e.g. press)
  • Cooling Water 8–35l/min at 25°C (dependent on transformer type)
  • Protection Class IP54
  • Maximum Number of Welding Positions 8
  • Maximum Number of Servo Axes 18