It / IOCÂ Instantaneous Overcurrent fault in Toshiba drive
It / IOC Instantaneous Overcurrent (Load) fault in Toshiba drive
Description "It" stands for **I** (Current) **t** (Time), typically representing an instantaneous accumulation of current limit. Unlike the standard "OC" (Hardware Short) or "OL" (Long-term Thermal), "It" is a predictive fault. It triggers when the current rises extremely fast—faster than a normal load ramp—but hasn't yet hit the absolute IGBT hard-limit. It often points to a mechanical shock load. Causes
1. Impact Load: A crusher or shredder hits a solid metal object, causing the motor to stop instantly.
2. Gearbox Failure: A tooth breaks in the gearbox, causing a momentary mechanical lockup.
3. Slack Chain: A loose chain grabs the sprocket teeth incorrectly, snapping tight and spiking torque. Solution Inspect the mechanics for "Shock" events. If the machine is a crusher or shredder, this might be a nuisance trip caused by the material. You can try adjusting the "Stall Prevention Level" (F601) to be less sensitive, allowing the drive to drop frequency momentarily to recover from the shock instead of tripping.
Check the "Current Detection Filter" parameter. Increasing the filter time constant can smooth out the "It" curve, ignoring millisecond spikes while still protecting against sustained jams.
Description "It" stands for **I** (Current) **t** (Time), typically representing an instantaneous accumulation of current limit. Unlike the standard "OC" (Hardware Short) or "OL" (Long-term Thermal), "It" is a predictive fault. It triggers when the current rises extremely fast—faster than a normal load ramp—but hasn't yet hit the absolute IGBT hard-limit. It often points to a mechanical shock load. Causes
1. Impact Load: A crusher or shredder hits a solid metal object, causing the motor to stop instantly.
2. Gearbox Failure: A tooth breaks in the gearbox, causing a momentary mechanical lockup.
3. Slack Chain: A loose chain grabs the sprocket teeth incorrectly, snapping tight and spiking torque. Solution Inspect the mechanics for "Shock" events. If the machine is a crusher or shredder, this might be a nuisance trip caused by the material. You can try adjusting the "Stall Prevention Level" (F601) to be less sensitive, allowing the drive to drop frequency momentarily to recover from the shock instead of tripping.
Check the "Current Detection Filter" parameter. Increasing the filter time constant can smooth out the "It" curve, ignoring millisecond spikes while still protecting against sustained jams.
Comments
Post a Comment