Agilent Technologies E3633A, E3634A Extending the Voltage and Current Range, Series Connections

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Extending the Voltage and Current Range

Extending the Voltage and Current Range

The power supply may be able to provide voltages and currents greater than its rated maximum outputs if the power-line voltage is at or above its nominal value. Operation can be extended up to 3% over the rated output without damage to the power supply, but performance can not be guaranteed to meet specifications in this region. If the power-line voltage is maintained in the upper end of the input voltage range, the power supply will probably operate within its specifications. The power supply is more likely to stay within specifications if only one of the voltage or current outputs is exceeded.

Series Connections

Series operation of two or more power supplies can be accomplished up to the output isolation rating of any one supply to obtain a higher voltage than that available from a single supply. Series connected power supplies can be operated with one load across both power supplies or with a separate load for each power supply. The power supply has a reverse polarity diode connected across the output terminals so that if operated in series with other power supplies, damage will not occur if the load is short-circuited or if one power supply is turned on separately from its series partners.

When series connection is used, the output voltage is the sum of the voltages of the individual power supplies. The current is the current of any one power supply. Each of the individual power supplies must be adjusted in order to obtain the total output voltage.

Parallel Connections

Two or more power supplies being capable of CV/CC automatic cross over operation can be connected in parallel to obtain a total output current greater than that available from one power supply. The total output current is the sum of the output currents of the individual power supplies. The output of each power supply can be set separately. The output voltage controls of one power supply should be set to the desired output voltage; the other power supply should be set for a slightly higher output voltage. The supply with the higher output voltage setting will deliver its constant current output, and drop its output voltage until it equals the output of the other supply, and the other supply will remain in constant voltage operation and only deliver that fraction of its rated output current which is necessary to fulfill the total load demand.

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