Robotics in Manufacturing
SRVO-131

SRVO-131: LVAL / LVAL (PS) alarm (PS control voltage low)

The control supply voltage inside the servo power supply (αiPS) is abnormally low - the power supply's own electronics are underfed.

What it means

The control supply voltage inside the servo power supply (αiPS) is abnormally low - the power supply's own electronics are underfed. Posts per amplifier. Hardware ladder, no configuration fix.

Common causes

Ranked by what technicians most often find, most likely first.

  1. Failed power supply (αiPS).
  2. Failed 6-axis amplifier.
  3. Failed power supply unit.

How to fix it

  1. Replace in FANUC's order: αiPS power supply, then the 6-axis amplifier, then the power supply unit. Power-cycle to clear between attempts.