Siemens Bsm B3 Schematic 〈Browser VERIFIED〉

Check the reverse-bias continuity of the freewheeling diode. If it is shorted, it will cause an immediate overcurrent fault across the DC bus upon activation.

Connects to one terminal of the external braking resistor. Gate (G): Connects to the gate drive control circuit. 2. The Freewheeling Diode (FWD) siemens bsm b3 schematic

Unlike cheap VFDs, the BSM B3 uses precision DC current transducers (or shunt resistors) on the output phases. On the schematic, look for low-ohm (e.g., 1mOhm) resistors in the emitter leg of the bottom IGBTs. These feed into a differential amplifier to send analog signals (typically 0-10V or 20mA) back to the control card for torque/current regulation. Check the reverse-bias continuity of the freewheeling diode

Typically 10k Ohm or 1k Ohm Platinum/Nickel sensors. Wiring requires a two-wire connection to the input terminal and the shared sensor common. Gate (G): Connects to the gate drive control circuit