LOAD CONSIDERATIONS

This section provides information on operating your supply with various types of loads connected to its output.

PULSE LOADING

The power supply will automatically cross over from constant- voltage to constant current operation in response to an increase (over the preset limit) in the output current. Although the preset limit may be set higher than the average output current, high peak currents (as occur in pulse loading) may exceed the preset cur- rent limit and cause cross over to occur. If this cross over limiting is not desired, set the preset limit for the peak requirement and not the average.

REVERSE CURRENT LOADING

An active load connected to the power supply may actually deliver a reverse current to the power supply during a portion of its operating cycle. An external source can not be allowed to pump current into the supply without loss of regulation and possi- ble damage to the output capacitor of the power supply. To avoid these effects, it is necessary to preload the supply with a dummy load resistor so that the power supply delivers current through the entire operating cycle of the load devices.

Figure 16. Reverse Current Loading Solution

OUTPUT CAPACITANCE

An internal capacitor, connected across the output terminals of the power supply, helps to supply high-current pulses of short duration during constant voltage operation. Any capacitance added externally will improve the pulse current capability, but will decrease the safety provided by the current limiting circuit. A high-current pulse may damage load components before the average output current is large enough to cause the current limit- ing circuit to operate.

The effect of the output capacitor during constant current opera- tion are as follows:

a.The output impedance of the power supply decreases with increasing frequency.

b.The recovery time of the output voltage is longer for load resistance changes.

c.A large surge current causing a high power dissipation in the load occurs when the load resistance is reduced rapidly.

REVERSE VOLTAGE LOADING

A diode is connected across the output terminals with reverse polarity. This diode protects the output electrolytic capacitors and the series regulator transistors from the effects of a reverse volt- age applied across the output terminals. For example, in series operation of two supplies, if the AC is removed from one supply, the diode prevents damage to the unenergized supply which would otherwise result from a reverse polarity voltage.

Since series regulator transistors cannot withstand reverse volt- age, another diode is connected across the series transistor. This diode protects the series regulators in parallel or auto-parallel operation if one supply of the parallel combination is turned on before the other.

BATTERY CHARGING

The power supply's OVP circuit contains a crowbar SCR, which effectively shorts the output of the supply whenever the OVP trips. If an external voltage source such as a battery is connected across the output, and OVP inadvertently triggered, the SCR will continuously sink a large current from the source; possibly damaging the supply. To avoid this a diode must be connected in series with the output as shown in Figure 17.

Figure 17. Recommended Protection Circuit for

Battery Charging

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Agilent Technologies Agilent E3617A Serials KR83502522, Agilent E3616A Serials KR83502651 service manual Load Considerations
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Agilent E3614A Serials KR83503035, Agilent E3617A Serials KR83502522, Agilent E3615A Serials KR83506197, Agilent E3616A Serials KR83502651 specifications

Agilent Technologies is a leading player in the field of electronic test and measurement devices, providing essential tools for engineers and scientists. Among their array of power supplies, models such as the Agilent E3616A, E3615A, E3617A, and E3614A stand out for their exceptional performance, reliability, and technological features.

The Agilent E3616A is a precision DC power supply known for its ability to deliver a maximum output of 60V and 3A. Its serial number, KR83502651, signifies its unique identity. This model is particularly valued in laboratory environments due to its advanced programming capabilities. It offers a comprehensive range of output voltage and current settings, making it versatile for various applications. One of its main features is the built-in 6V at 3A output, which can be useful for testing other devices.

Similarly, the Agilent E3615A, with the serial number KR83506197, provides an excellent blend of performance and functionality. It is capable of delivering up to 30V and 3A across its outputs. This model excels in its low noise operation, which is crucial for sensitive electronics testing. Furthermore, the user-friendly interface allows for quick adjustments and settings retrieval, making it a favorite among engineers. The E3615A is designed to support a wide range of applications, from component testing to powering devices in research settings.

The Agilent E3617A, identifiable by its serial number KR83502522, is another high-performance model that offers a maximum output of 30V and up to 3A. It features built-in read-back capabilities, enabling engineers to monitor the actual voltage and current supplied to the load. The E3617A stands out for its programmable output, allowing automated testing sequences to be implemented with ease.

Lastly, the Agilent E3614A, with the serial number KR83503035, is a cost-effective option without sacrificing quality. This model offers an output of up to 30V and 3A while maintaining stability and precision. Its compact design makes it easy to integrate into crowded workspaces or test setups. The E3614A is designed for durability, ensuring reliable performance over time, making it an excellent choice for both education and industrial applications.

With their high-precision outputs, easy programmability, and user-friendly interfaces, these Agilent power supplies serve as essential tools for a variety of testing and research needs, reflecting Agilent Technologies' commitment to quality and innovation in electronic measurement solutions.
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