Gradient Power Amplifier (GPA)

Drives the X, Y, Z gradient coils. High-current, liquid-cooled, capacitor-backed. One of the most expensive subsystems on the Symphony.

Fits

• MAGNETOM Symphony

Diagnosis

• Axis-specific fault codes → pull the log, check which board
• Recurrent overtemp even after chiller service → capacitor bank or internal flow
• Never run a Symphony with a flagged gradient. You will cook it.

Field notes

See field-guide/siemens-magnetom-symphony.