Agilent Technologies 6812B manual Capacitance in μF, Ipeak setting, 3. Peak Inrush Current Example

General Information - 1

♦as voltage increases, the Ipeak setting needs to be decreased.

♦as frequency increases, the Ipeak setting can be increased.

♦as load resistance decreases, the Ipeak setting needs to be decreased.

Note that the purpose of programming the Ipeak current is to prevent the unit from activating its internal protection mode as a result of exceeding the SOA limits, and turning the output off. These initial settings may have to be reduced if the SOA circuit trips when the output is turned on. Sometimes trial and error must be used to arrive at the proper values of Ipeak.

Table 1-4. Recommended Ipeak Settings as a Function of Loop Capacitance

Capacitance in μF

127 V	254 V
≤ 1100	500
1200	-
1700	700
5000	1000
> 5000	> 1000

Ipeak setting

80A

60A

50A

45A

<45 A

The following waveform illustrates the inrush current capability of the ac source. The peak current is limited during inrush in accord with table 1-3 to keep the ac source from turning its output off. Note that the output current waveform returns to its normal shape when the current drops below the peak current limit setting.

VOLTAGE IS

UNDISTORTED

		(115	Vrms)
CURRENT	VOLTAGE		PEAK CURRENT
WAVEFORM	WAVEFORM
		<	45 A

I PEAK=45A

0

Figure 1-3. Peak Inrush Current Example

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