Robotics in Manufacturing
SRVO-049

SRVO-049: OHAL1 alarm (amplifier overheat)

The thermostat in the amplifier's transformer tripped - the amplifier itself is overheating.

What it means

The thermostat in the amplifier's transformer tripped - the amplifier itself is overheating. Posts per amplifier (axes 1-2 or 1-2-3). Cooling problem or workload problem; power-cycle to clear.

Common causes

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

  1. Stopped fan or clogged vents/filters on the cabinet.
  2. Punishing duty cycle heating the amplifier beyond its cooling capacity.
  3. Amplifier or thermostat fault if it trips cool.

How to fix it

  1. Check cabinet fans spin and vents are clear; clean or replace filters.
  2. If the operating condition is severe, relax the duty where possible.
  3. Persistent tripping with good cooling and reasonable duty goes to the maintenance manual's amplifier checks.

Quick facts

Category
Servo
Affected series
R-30iB; R-30iB Mate; R-30iB Plus; R-30iB Mate Plus
Alarm family
SRVO

Related codes

Verified against FANUC documentation (B-83284EN-1).Last reviewed: 2026-07-09.Editorial process