CV Mode vs. CC Mode

Programming Overcurrent Protection

When enabled, overcurrent protection removes the power supply output whenever it goes into CC operation. This prevents the supply from indefinitely supplying the full programmed current to the load.

Setting The OCP Protection

To activate overcurrent protection, press . The OCP annunciator will light and power supply will continue to operate

normally until it is forced into CC operation. If that occurs, the OCP circuit will trip and the power supply will remove its output.

Checking OCP Operation

The easiest way to check this operation at any specified current is to increase the load current beyond the programmed current value and, if necessary, decrease the programmed voltage. This will force the power supply into the CC mode (see Figure 5-2). When OCP trips, the Prot annunciator will light and the power supply output will drop to zero.

There is now no power supply output due to an overcurrent condition. To verify this, press and observe that the display indicates OC.

Clearing The OCP Condition

With the OCP tripped, return to the meter mode and try to clear the condition by pressing . Nothing will appear to

happen because the reason for the condition has not been removed. Thus, as soon as the circuit is cleared, it trips again. You can clear the OC condition by:

■Increasing the load resistance to lower the output current below the programmed current value, or

■By raising the programmed current to a value above that required by the load.

Clear the fault by either of the above methods. Then clear the OCP circuit by pressing . The Prot annunciator will go off and the power supply output will be restored to normal.

If desired, you can also restore the output by disabling the OCP function (press to turn off the OCP annunciator). This restores the output but does not clear any condition that may have caused OCP to trip.

Note	Under certain conditions, the OCP circuit may fail to clear because load demand occurs before the power
	supply has time to build up the required output current capacity. In such cases, disable the output (press
	before clearing the OCP circuit). After OCP is cleared, enable the power supply output.

Once you program a voltage (VS) and a current (IS) in Figure 5-2, the power supply will try to maintain itself in either CV or

CCmode, depending on the impedance of the load (RL). If the load demands less current than Is, operation will be in CV mode with the voltage maintained at Vs. The output current will be at some value below Is as determined by VS ⎟ RL.

If the current increases beyond IS (see RL2), the supply will switch to CC mode by varying its output voltage to maintain a constant current value of Is. As more current is demanded, the voltage decreases to maintain the increased current level. If the load current increases to the maximum output of the power supply, the output voltage will be maintained at a near-zero level.

Front Panel Operation 91

668xA, 669xA, 667xA, 664xA, 665xA specifications

Agilent Technologies has long been a pioneer in the production of high-performance electronic test and measurement instruments, particularly in the field of power sources. Among its notable offerings are the Agilent 667xA, 669xA, 665xA, 664xA, and 668xA series of power supplies. These instruments are designed to provide stable, reliable power for a variety of applications, including electronic testing, industrial processes, and research laboratories.

The Agilent 667xA series is characterized by its programmability and advanced measurement functions. These power supplies support a wide range of output voltages and currents, allowing for flexible configurations that cater to different testing needs. The built-in measurement capabilities enable users to monitor the voltage, current, and power with high precision, which is essential for ensuring optimal performance in electronic applications.

The Agilent 669xA series stands out with its high-power outputs, making it suitable for demanding applications. These power supplies deliver high voltage and current levels, making them ideal for testing high-performance devices, such as power amplifiers and motor drives. Additionally, the 669xA series includes features such as overvoltage protection and complex output sequencing to enhance the safety and reliability of the testing process.

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Overall, the Agilent 667xA, 669xA, 665xA, 664xA, and 668xA power supplies provide a comprehensive range of solutions for diverse electronic testing needs. With their advanced features, superb measurement capabilities, and robust performance, these instruments empower engineers and researchers to conduct their work with confidence, precision, and efficiency.

Agilent Technologies 664xA, 665xA, 667xA CV Mode vs. CC Mode, Programming Overcurrent Protection

Models: 668xA 669xA 667xA 664xA 665xA