Product Description:

The PST6100.332-L is a Bosch Rexroth Indramat thyristor power unit supplied within the PST Thyristor Power Units series. It switches power to resistance heaters and similar loads in industrial automation, using phase-angle or zero-cross firing to regulate energy flow. By integrating high-current thyristor stacks with control electronics, the module provides fast, solid-state power modulation that replaces electromechanical contactors and improves response time in closed-loop temperature or process controllers. Solid-state switching also reduces contact wear associated with mechanical devices and helps support stable output control during frequent cycling.

The power stage dissipates 70 W of heat into the cabinet during nominal operation, so forced airflow must keep internal temperatures below the unit's component limits. All logic circuits are energized from a 24 V DC control supply that is isolated from the load side for safety and noise immunity. The line side can conduct a continuous 130 A of system current, allowing the unit to drive multi-zone heater banks without series derating. Incoming cooling air must not exceed 45 °C to prevent thermal foldback of the thyristor junctions. Line and load conductors up to 50 mm² can be landed on the power terminals, allowing cable selection that matches breaker and transformer ratings. This arrangement supports straightforward integration in enclosed control cabinets where wiring space and thermal airflow both matter.

The firing board sustains a maximum duty cycle of 50%, so thermal management must account for half-wave conduction when sizing heat sinks and cabinet fans. When supplied from transformers up to 76 kVA, the unit maintains trigger stability without false commutation. An IP20 protection rating indicates guarded finger-safe terminals but no sealing against dust ingress, which aligns with its recessed mounting style that requires a minimum 100 mm clearance for airflow. Reliable operation is specified up to 2000 m elevation, where reduced air density still provides sufficient cooling headroom, and metal-oxide varistors clamp transient line surges that could otherwise puncture the thyristor junctions. Clear airflow around the recessed mounting area remains important because unrestricted ventilation helps the power section shed heat during continuous heater control.