Product Description:

The PST6100.355-L belongs to the PST Thyristor Power Units series produced by Bosch Rexroth Indramat. This thyristor power unit regulates current supplied to industrial resistance heaters and transformer-fed loads, allowing precise energy control in automated processes that require two-phase power modulation. By switching silicon-controlled rectifiers under closed-loop commands, the unit provides repeatable power cycles for melting, annealing, and other heat-based operations. Because the switching action is electronically controlled, the load receives regulated energy rather than abrupt full-line switching.

The control electronics run on 24 V DC, and the main thyristor stack handles a nominal system current of 130 A across its two input phases. To dissipate the basic cabinet loss of 70 W, the assembly uses an air-cooled heat sink inside a cabinet rated at IP54 against dust and splashing water. That cooling arrangement removes heat from the power section without requiring liquid cooling hardware. Connection lugs accept conductors up to 50 mm², and a recessed mounting frame supports secure installation in the panel. For networked sequencing, the unit incorporates an INTERBUS timer, while an MOV network clamps transient overvoltages on the supply. Integrated temperature monitoring protects the semiconductors, and the power section can drive transformers up to 76 kVA without derating.

During production cycles, the thyristors may be energized for only 50% of the period, a duty limit that prevents excess junction temperature. Continuous operation is permitted in ambient air up to 55 °C, provided the incoming cooling stream stays below 45 °C and the installation altitude does not exceed 2000 m above sea level. The duty restriction and cooling conditions must be observed together so the semiconductor junctions remain within their intended operating range. Internal bus bars are guarded by a protection rating of IP20, so live parts remain finger-safe once the front panel is removed.