F30005 — Power unit: Overload I2t

F30005 (Power unit: Overload I2t) is raised when the I2t thermal image of the power unit reaches its limit: the overload utilization in r0036 stands at 100 %. The drive tracks the thermal loading of the power unit continuously from the output current; when the power unit draws more than its permissible rated current for an inadmissibly long time, or the application exceeds the permissible load duty cycle, the thermal image saturates and the drive trips. The stored fault value shows the I2t utilization in r0949 as a decimal number, where 16384 corresponds to 100 %. The manuals describe the same condition and the same causes for the power unit everywhere; they differ only in the extra remedy steps they print.

• The power unit was overloaded — the I2t utilization in r0036 has reached 100 %.
• The permissible rated power unit current was exceeded for an inadmissibly long time.
• The permissible load duty cycle was not maintained.

1. Reduce the continuous load on the drive.
2. Adapt the load duty cycle so that the permissible load duty cycle of the power unit is maintained.
3. Check the rated currents of the motor and the power unit against each other; the manual names the rated power unit power (r0206) and the rated motor power (p0307) alongside this step.
4. Reduce the current limit (p0640) — a step printed by the G120, G120XA, G115D and G120C manuals.
5. During operation with the U/f characteristic, reduce the integral time of the current limiting controller (p1341) — again printed by the G120, G120XA, G115D and G120C manuals.
6. Increase p0294 — the I2t overload alarm threshold of the power unit; the VECTOR drive objects of the G130/G150 and S120/S150 manuals additionally list this step.

• The drive writes the fault value into r0949; interpret it as a decimal number.
• The value is the I2t utilization of the power unit, scaled so that 100 % = 16384.

• r0036 — shows the current I2t utilization of the power unit; F30005 is raised when it reaches 100 %.
• r0949 — holds the fault value of F30005; read it as the decimal I2t utilization (100 % = 16384) to see how far the thermal image was loaded.
• p0640 — current limit; reduce it so the power unit draws less current.
• p1341 — integral time of the current limiting controller; reduce it when the drive operates with the U/f characteristic.
• p0294 — I2t overload alarm threshold of the power unit; the G130/G150 and S120/S150 entries for the VECTOR drive objects advise increasing it.
• r0206 — rated power unit power; displayed when checking that the power unit rating matches the motor.
• p0307 — rated motor power; the counterpart to r0206 when comparing motor and power unit ratings.

The drive opens OFF2: the power unit switches off and the motor coasts to a standstill. The fault has to be acknowledged before the drive will run again, and it can be acknowledged immediately. If the load condition that drove r0036 to 100 % is still present, the drive trips again as soon as the thermal image fills up once more — remove the overload before restarting.