Product Overview

The Siemens 6DD2920-0AL0​ is an AUL2 trigger monitoring and evaluation logic module, purpose-built for the power section of SIMADYN D thyristor converter stacks. Its first critical distinction — and the one that trips up engineers new to the platform — is where it lives: the 6DD2920-0AL0​ does not​ plug into the SIMADYN D Euro-rack backplane alongside PM4/PM5/PM6 processors. Instead, it mounts as a daughter/sub-module onto a SAV21 or SAV22 power interface module (Leistungsteil-Interface), which itself sits in the power/trigger chain between the SIMADYN D processor’s IT (impulse/trigger) board and the thyristor valve gates. The AUL2 designation comes from the German AuswertungsLogik (evaluation logic) for trigger monitoring — the module’s job is to watch what the firing pulses are actually doing at the valve level and kill them the moment something drifts.What the Siemens 6DD2920-0AL0​ does internally is pure hardware: two independent trigger-monitoring channels, each accepting 200 mA–2 A firing current range, with dV/dt sensing on the thyristor anode–cathode voltage to detect false turn-on, pulse loss, short-circuit, and commutation failure. Response is <10 µs from fault detect to pulse-block — completely bypassing the PM’s software scan cycle. In a rolling-mill main drive or HVDC valve group where a single thyristor misfire cascades into a stack-killer fault, that hardware-level fast trip is the difference between “alarm + clean shutdown” and “blown fuses + week-long rebuild.” The 6DD2920-0AL0​ gets its 24 V DC from the SAV21/SAV22 carrier’s isolated internal rail, talks to the carrier via the local pin header (not PROFIBUS, not C-Bus, not L-Bus), and raises a hardware alarm output plus LED per channel when something trips.Critical for spare-pool managers: Siemens canceled the 6DD2920-0AL0​ effective April 1, 2008​ with the explicit status “abgekündigt ohne Ersatz” — canceled without substitution​ . There is no AUL3, no TDC-era replacement, no SINAMICS analog that drops onto SAV21/SAV22. If your SIMADYN D power section still runs SAV21/SAV22 (which most 1995–2008 vintage mills/hydro/HVDC do), the Siemens 6DD2920-0AL0​ is a dead-end spare — NOS or verified-pull is the only path, and the “no sub” status means you can’t even cross-specify.

Technical Specifications