VSD trips on overcurrent / overload
The drive trips with an overcurrent or overload code — on start, on acceleration, or under running load. It may restart and trip again on the same point in the cycle.
Safety first
Overcurrent trips can indicate a short or earth fault on the motor or cable. Prove dead and discharge the DC bus before testing output cabling. Never reset repeatedly into a hard fault.
Isolate, lock out / tag out, and prove dead before working unless a live test is specifically required, authorised, and carried out under proper supervision. Always follow local regulations, your site procedures, and the equipment manufacturer's documentation.
Apprentice mode
Full walk-through — the why, what readings mean, mistakes & safety.
Likely causes
Ranked from most to least likely.
- 1
Mechanical overload or jam on the driven equipment
Most likelyIf the load is jammed, sticking, or the inertia is too high for the accel ramp, current spikes and the drive trips to protect itself and the motor.
- 2
Acceleration ramp too fast for the load
#2A ramp time set shorter than the load's inertia can tolerate forces high current during accel and trips at the same point each time.
- 3
Output cable or motor fault (short / earth fault)
#3A phase-to-phase or phase-to-earth fault in the motor or its cable causes an immediate overcurrent the instant the drive outputs.
- 4
Incorrect motor data / control mode
#4Wrong nameplate parameters or an un-tuned vector mode makes the drive mis-estimate current and trip, especially at low speed.
- 5
Undersized drive for the duty
Least likelyA drive rated below the load's real demand will trip on legitimate peaks the application needs.
Reports are saved on this device to reflect what you actually find.
Testing sequence
Work through one test at a time. Expected reading and what each result means.
On the tools? Job Mode shows one test at a time with thumb-sized buttons — your place and readings carry straight over.
Enter Job ModeNote exactly when it trips — at the instant of output, during accel, or under steady load — and read the exact fault code/value.
A consistent trip point you can describe and a clear code.
Trip pattern points you to a cause group (instant=short, accel=ramp/inertia, load=mechanical).
If it's random, suspect intermittent wiring or a marginal motor fault.
View all expected readings at once
Fault-finding flowchart
The same logic as a decision tree.
- 1start
VSD trips on overcurrent
→ step 2 - 2decision
Does it trip the instant it outputs (before the motor moves)?
Yes→ step 3No→ step 4 - 3result
Suspect a motor/cable short or earth fault. Isolate and insulation-test before re-running.
- 4decision
Does it trip during acceleration?
Yes→ step 5No→ step 6 - 5result
Lengthen accel ramp / check inertia and motor data + tune.
- 6decision
Is running current within drive/motor rating?
Yes→ step 7No→ step 8 - 7result
Check motor data/control mode and drive sizing for the duty.
- 8result
Genuine overload on the driven equipment — hand to mechanical.
Common mistakes apprentices make
- Resetting into a hard overcurrent repeatedly, risking the drive and motor.
- Blaming the drive when the driven machine is mechanically jammed.
- Shortening accel ramps to 'speed things up' and then chasing the resulting trips.
- Skipping motor/cable insulation tests after an instant-on overcurrent.
When to stop & escalate
Confirmed motor or cable short/earth faults, or a load that is genuinely overloaded, should go to the appropriate repair/mechanical team. Repeating drive faults that don't match wiring or load findings should be taken to the manufacturer's documentation/support with the exact code.
If you're past your competence, authorisation, or the safe limits of the job — stop and hand it on. There's no fault worth getting hurt over.
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Related faults
VSD powered up but won't start the motor
The drive is energised and the display is alive, but it won't run the motor. No fault may be shown — it just sits in 'ready' or 'stopped' and ignores the start command.
Motor overload keeps tripping
The thermal/electronic overload trips repeatedly, either on start or after the motor has run for a while. Resetting only buys you a short run before it trips again.
Three-phase equipment single-phasing (lost a phase)
Three-phase equipment is misbehaving — motors humming, struggling, overheating, or tripping — because one phase has been lost somewhere between the supply and the load.
Learn the theory
How the gear and circuits behind this fault actually work.