OL1 / OL2 Motor Overload / Drive Overload fault in Toshiba drive
OL1 / OL2 Motor Overload / Drive Overload fault in Toshiba drive
Description OL faults relate to thermal capacity. OL1 is the "Electronic Motor Thermal Protection" calculation, meaning the VFD calculates that the motor is running too hot based on the current draw over time. OL2 indicates the VFD internal components (heatsink/IGBTs) are thermally overloaded. This functions similarly to a traditional bimetallic overload relay but is calculated digitally. The trip curve is inverse-time: the higher the current, the faster it trips. It protects the insulation of the motor from melting. Causes
1. Excessive Load: The motor is physically doing more work than it is rated for (e.g., dull cutting blades, clogged filters, worn bearings).
2. Low Speed Operation: Running a standard AC induction motor at very low speeds (below 30Hz) without a cooling fan. The shaft-mounted fan does not spin fast enough to cool the motor, yet the current remains high.
3. Wrong Parameters: The "Motor Rated Current" (FLA) parameter is set incorrectly (too low).
4. V/f Pattern: Incorrect voltage-to-frequency ratio causing over-fluxing. Solution First, check the parameter settings. Navigate to the motor parameters and ensure the "Motor Rated Current" (often F415 or similar depending on the Toshiba series) matches the motor nameplate exactly. If the parameter is set to 5A but the motor is 10A, it will trip prematurely.
Next, analyze the mechanical load. Check amperage draw using the drive display while running. If the amps are constantly near or above the motor's nameplate rating, the motor is undersized or the machine is jammed. Check belts, gears, and lubrication.
If the application requires running at low speeds (e.g., 10Hz) for long periods, a standard TEFC motor will overheat. You must either install an auxiliary cooling fan (blower cooling) on the motor or upgrade to an "Inverter Duty" motor capable of 1000:1 turndown.
Alternatively, adjust the "Electronic Thermal Protection Level" parameter. Caution: Only increase this if you are certain the motor is not actually overheating. You can also change the "Stall Prevention" level, which automatically lowers the frequency if the current gets too high, preventing a hard fault trip by sacrificing some speed.
Description OL faults relate to thermal capacity. OL1 is the "Electronic Motor Thermal Protection" calculation, meaning the VFD calculates that the motor is running too hot based on the current draw over time. OL2 indicates the VFD internal components (heatsink/IGBTs) are thermally overloaded. This functions similarly to a traditional bimetallic overload relay but is calculated digitally. The trip curve is inverse-time: the higher the current, the faster it trips. It protects the insulation of the motor from melting. Causes
1. Excessive Load: The motor is physically doing more work than it is rated for (e.g., dull cutting blades, clogged filters, worn bearings).
2. Low Speed Operation: Running a standard AC induction motor at very low speeds (below 30Hz) without a cooling fan. The shaft-mounted fan does not spin fast enough to cool the motor, yet the current remains high.
3. Wrong Parameters: The "Motor Rated Current" (FLA) parameter is set incorrectly (too low).
4. V/f Pattern: Incorrect voltage-to-frequency ratio causing over-fluxing. Solution First, check the parameter settings. Navigate to the motor parameters and ensure the "Motor Rated Current" (often F415 or similar depending on the Toshiba series) matches the motor nameplate exactly. If the parameter is set to 5A but the motor is 10A, it will trip prematurely.
Next, analyze the mechanical load. Check amperage draw using the drive display while running. If the amps are constantly near or above the motor's nameplate rating, the motor is undersized or the machine is jammed. Check belts, gears, and lubrication.
If the application requires running at low speeds (e.g., 10Hz) for long periods, a standard TEFC motor will overheat. You must either install an auxiliary cooling fan (blower cooling) on the motor or upgrade to an "Inverter Duty" motor capable of 1000:1 turndown.
Alternatively, adjust the "Electronic Thermal Protection Level" parameter. Caution: Only increase this if you are certain the motor is not actually overheating. You can also change the "Stall Prevention" level, which automatically lowers the frequency if the current gets too high, preventing a hard fault trip by sacrificing some speed.
Comments
Post a Comment