Danfoss VLT PowerCards are internal power-section boards used in VLT frequency converters and are treated as critical hardware within the drive’s protection and fault-monitoring system.
These boards include a switch-mode power supply that generates internal control voltages, with the monitored supply rails depending on whether the unit is operating from a 24 V backup supply or from the main AC input. The power card is also tied to thermal supervision and gate-drive communication, including heat-sink/IGBT temperature signaling and interconnections to the gate-drive circuitry used in diagnostics. In higher-power or multi-module drive configurations, power-card-related faults can be reported by module position so the system can identify which power section generated the alarm. Correct matching and installation of related scaling/connection hardware is also required, and the drive can generate a power-section configuration fault when that hardware is missing, incompatible, or improperly installed.
