Power
Robot drops out mid-shift with a power alarm
The robot faults on a servo power alarm and needs a power cycle to clear.
Most likely causes
DC link overvoltage (SRVO-044 / DCHVAL)
The DC bus voltage inside the servo power circuit went abnormally high. Regenerative energy from heavy decel or vertical axes can spike the link.
Low control voltage to the servo amplifier (SRVO-047 / LVAL)
The +5V-class control supply feeding the amplifier's electronics fell below spec. This traces to the servo amplifier or the power supply unit.
Incoming supply voltage high (feeds SRVO-044)
Check the input voltage to the controller against rating and the three-phase input at the amplifier. Above 240 VAC, high acceleration/deceleration can trigger the overvoltage alarm.
Load above the axis rating (feeds SRVO-044)
If the machine load exceeds rating, accumulated regenerative energy can produce the overvoltage alarm even when three-phase input is within spec.
Where to start
- Read the active alarm and note whether the code is SRVO-044 (DCHVAL) or SRVO-047 (LVAL). They point in opposite directions.
- If the alarm recurs after a power cycle, this becomes a controller power-circuit diagnosis for qualified personnel.
- Go to the matching alarm page for the diagnosis steps: SRVO-044 or SRVO-047.
Still stuck? Start with the closest matching alarm reference.
Related alarm codes
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