Overload Protection Functions

■ Current limiting function

This function is activated if the PCR-M's output current exceeds the current limit value (maximum setting: 1.05 times the rated maximum current). If the current limiting function is activated, OVER LOAD illuminates, and the output voltage gradually drops. If this condition lasts approximately 3 seconds, the output is automatically turned off.

■ Peak current and power monitor functions

This function is activated if the PCR-M's peak current exceeds three times the rated maximum current. If a current exceeding three times the rated maximum current flows through the load, OVER LOAD illuminates, and the output voltage drops or the waveform is distorted. If this condition lasts approximately 10 seconds, the output is automatically turned off.

■ Causes of and remedies for overload status

If the overload protection function is activated, take the remedies below. Then, wait at least 1 minute before resuming operations.

When the cause of the overload is eliminated, the protection function is automatically deactivated.

For linear loads

Overload Condition		Remedy
Gradual output current increase	If the voltage drops as shown in Fig. A, the current limiting function is activated. If the output voltage waveform is distorted as shown in Fig. B-1 or B-2, the internal protection function is activated.	If the current limit value is set low, change the setting. If the rated maximum current is exceeded, reduce the load.
Sudden output current increasev	If the output voltage waveform is distorted as shown in Fig. B-1, B-2, or C, the internal protection function is activated.

For capacitor-input rectifying loads

Overload Condition		Remedy
Output current increase	If the voltage drops as shown in Fig. A, the current limiting function is activated.	If the current limit value is set, change the setting. If the rated maximum current is exceeded, reduce the load.
	If the voltage waveform is distorted as shown in Fig. C, the internal protection function is activated due to the output peak current.	Reduce the peak current.

For loads that draw an inrush current

Overload Condition		Remedy
When voltage is applied to the load or when the voltage suddenly changes	If the voltage waveform is distorted as shown in Fig. C, the internal protection function is activated due to the inrush current.	Reduce the inrush current.

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