APM
All alarm codes
ALARM 25

MAIN POWER SUPPLY MALFUNCTION (1, 0, &0061)

Main power supply fault — capacitor bank, regen resistor, or input rectifier on the power module is failing.

Controls
Mazatrol 640T
Machine series
Mazak lathes on M640T

Causes

  1. Main power supply fault — capacitor bank, regen resistor, or input rectifier on the power module is failing.

    • Fabian Achavalyoutube
      M640T: Troubleshooting alarm 25 MAIN POWER SUPPLY MALFUNCTION ( 1, 0, &0061). Part #1

How to clear it

  1. 1

    Disable the spindle drive temporarily and test X, Z, and turret axes independently to isolate which drive load is tripping the power supply (per Part 2 of the series).

    • Fabian Achavalyoutube
      25 Main Power Supply Malfunction. How to disable the Spindle Drive and test X & Z & Turret

Confidence: high · Two-part video series from a Mazatrol service tech specifically on this alarm + alarm string.

First sourced: 5/21/2026

Related alarms

Same control or a nearby code on the same machine.