1. Alert Function

An audio-visual low-frequency alarm is triggered when the lift capacity reaches or exceeds 90% (can be manually adjusted) of the rated load.

2. Alert Protection

When the lifting capacity reaches or exceeds 100% (adjustable manually) of the rated load, a high-frequency sound and light alarm is triggered. If the alarm is not cleared after a certain delay time (adjustable manually), the ascending circuit will automatically be disconnected, preventing lifting operations, while emitting a continuous long alarm sound and the alarm indicator light will flash at a high frequency.

3. Immediate Protection

When the lifting capacity exceeds or equals 110% (adjustable manually) of the rated load, immediately disconnect the lifting circuit, prohibit the lifting action, and simultaneously emit a continuous alarm sound and high-frequency blinking of the alarm indicator light.

4. Phase Sequence Protection

When the three-phase power supply phase sequence is incorrect, an audible and visual alarm is triggered, displaying the fault code. At the same time, the main power control contact and the rising circuit control contact are disconnected, prohibiting any operation.

5. Phase Protection

When the device is powered on, if either Phase A or Phase B is missing, the device will not operate due to the lack of working power. The normally open contact within the device,串联 in the crane control circuit, remains open, preventing the crane from lifting or lowering operations. However, there is no audible or visual alarm, nor any fault code display.

b. When the device is powered on, if the C phase is missing, an audible and visual alarm will sound, displaying a fault code. At the same time, the main power control contact and the rising circuit control contact will be disconnected, prohibiting any operation.

During the operation of the crane motor, an audible and visual alarm is triggered when a phase current is detected as zero. After a delay period (which can be manually set), a fault code is displayed, and the main power control contact and the lifting circuit control contact are disconnected, prohibiting any operation.

6. Short Circuit Protection

When any phase of the motor's working current exceeds or equals 600% of the rated current, an audible and visual alarm is triggered. If the alarm persists for 0.8 seconds without being cleared, a fault code will be displayed, and simultaneously, the main power control contact and the rising circuit control contact will be disconnected, prohibiting any operation.

7. Anti-locked Braking System (ABS) Protection

When any phase of the motor's working current exceeds or equals 400% of the rated current, an audible and visual alarm is triggered. If the alarm persists without being cleared within the startup time, a fault code is displayed, and simultaneously, the main power control contacts and the rising circuit control contacts are disconnected, prohibiting any operation.

8. Three-Phase Unbalance Protection

When the difference between any two phase currents is ≥60%, an audible and visual alarm is triggered. If the alarm persists for 5 seconds without being cleared, a fault code will be displayed, and the main power control contact and the rising circuit control contact will be disconnected, prohibiting any operation.

9. Under-voltage Protection

When the average voltage of the three-phase power supply is below the under-voltage set value, an audible and visual alarm is triggered. If the alarm persists for 5 seconds without being cleared, a fault code is displayed, and the main power control contact and the rising circuit control contact are disconnected, prohibiting all operations.

Overvoltage Protection

When the average voltage of the three-phase power supply exceeds the overvoltage set value, an audible and visual alarm is triggered. If the alarm persists for 5 seconds without being cleared, a fault code will be displayed, and the main power control and rising circuit control contacts will be disconnected, prohibiting all operations.

Overcurrent Protection

The overcurrent protection operates with inverse-time characteristics, allowing the protection time to be set according to user requirements. The current multiple corresponding to the sequence number and the protection time characteristics are detailed in the manual.