Product Description:

The PST6100.280-L is a thyristor power unit produced by Bosch Rexroth Indramat and assigned to the PST Thyristor Power Units series. Serving as a phase-angle controller, it modulates line power for resistance welders, heating elements, and other loads that require fast, repeatable current shaping in automated production lines. Its cabinet-mounted design allows a PLC to command weld energy profiles while the unit processes fieldbus timing signals to trigger silicon-controlled rectifiers with precise timing. This arrangement helps keep current delivery consistent during repetitive welding and heating cycles.

It receives low-voltage logic power at 24 V DC, and the thyristor stack can conduct a continuous line current of 130 A to the connected secondary. Transformers rated up to 76 kVA can be connected without exceeding the conduction limits of the semiconductors. Cabinet thermal rise is moderated by only 70 W of internal loss, and cooling uses a forced-draft air path with inlet air not hotter than 45 °C. For spot-weld sequencers, the built-in PROFIBUS timer synchronizes half-cycle firing pulses so welding heads observe a maximum on-time of 50%. Surge events on the line are shunted by a metal-oxide varistor network, and copper conductors up to 50 mm² can be landed on the power terminals under torque lugs.

The unit stands 463 mm high, spans 239 mm across the rail, and extends 280 mm in depth. With a mass of 12.5 kg, it can be secured to standard mounting plates without auxiliary brackets. The housing carries an IP20 degree of protection, so it must be installed inside an enclosure while remaining safe from accidental finger contact. Reliable performance is maintained at ambient temperatures up to 55 °C and elevations to 2000 m, provided the intake airflow meets the design requirement for the air-cooled path.