Input fuses
Low-cost line-side part to check when one phase is missing or unstable.
ABB ACS310 Fault 3130 — What It Means
Fault 3130 on the ABB ACS310 variable frequency drive indicates an input phase loss — one or more of the three input supply phases is missing or has dropped below the threshold the drive requires for stable operation. The ACS310 monitors input voltage symmetry; if any phase is absent or severely unbalanced, it faults to protect the internal rectifier and DC bus capacitors from unbalanced voltage stress.
Common Causes
- Blown input fuse on one phase — The most common cause. A single blown fuse in the incoming supply creates single-phase input on a three-phase drive.
- Loose or corroded input terminal connection — A loose lug at the drive’s L1, L2, or L3 terminal creates intermittent phase loss under load.
- Tripped breaker on one leg — A three-phase breaker with one tripped pole (common in thermal-magnetic breakers) creates the exact same symptom as a blown fuse.
- Upstream contactor with a failed contact — A worn contactor contact on one phase passes no current under load, even if it appears closed when de-energized.
Step-by-Step Fix
- Measure input voltage at the drive terminals — With a multimeter, measure L1-L2, L2-L3, and L1-L3 at the drive’s input terminals under load. All three readings should be equal (within 2%). A missing or low reading identifies the faulted phase.
- Check input fuses — Open the upstream disconnect and test all three input fuses with a multimeter. A blown fuse reads open. Replace if bad — always replace all three when one blows.
- Inspect input terminal connections — Check the torque on all L1/L2/L3 lug screws at the drive. Loose connections cause intermittent phase loss that gets worse under heat.
- Inspect the upstream contactor (if installed) — Check contactor contacts for pitting or burning on the affected phase. A failed contact often shows burn marks or unequal wear vs. the other phases.
- Reset the fault — After correcting the input issue, restore power and reset the ACS310 (press STOP/RESET on the keypad). Confirm 3130 does not return on restart.
Parts Often Needed
| Part | Notes |
|---|---|
| Input fuses (Class J or equivalent) | Match to ACS310 input current rating — replace all three |
| Input contactor | Replace if contacts are burned or pitted |
| Input terminal block | If lug damage is found during inspection |
Need Replacement Parts?
Before ordering, match the drive part to the model number, electrical rating, and failure symptom. Check current prices on Amazon - prices and availability change frequently.
When to Call a Pro
Phase loss diagnosis requires working in live panels with dangerous voltages. If you’re not qualified to work on industrial electrical enclosures with exposed live terminals, have a licensed electrician trace and repair the input circuit.