Over Frequency

Default value

• Dropout: 105% of the rated frequency.

• Pickup: 101% of the rated frequency.

Range

• The over frequency sensing range for a falling voltage (dropout) is 101%–120% of rated voltage.

• The over frequency sensing range for a return voltage (pickup) is 100%–115% of rated voltage.

Adjustable

The adjustable step for over frequency threshold is 0.5%.

Differential

• The default differential between dropout and pickup = 0.5% of rated frequency.

On LCD

• If minimum differential (0.5% of rated in default) rule is broken during dropout setting, the pickup value will be modified (pickup = dropout – 0.5% ) to keep the rule.

On Modbus

Dropout value is always accepted, if the pickup value do not comply the minimum gap, the pickup value will be modified to value (pickup = dropout – 0.5%).

Sequence of events

• When a sensor detects a frequency below the set dropout frequency for a period longer than the time delay, it deems the voltage is out of range.

• When the sensor detects a frequency at or above the pickup point, it deems the frequency as acceptable.