The compact Electronic DC loads EA-EL 9000 B series offer useful voltage, current and power ratings for a multitude of applications. All models support the four common regulation modes constant voltage (CV), constant current (CC), constant power (CP) and constant resistance (CR).
An FPGA based digital control circuit provides interesting features, such as a function generator for arbitrary curves and a table based XY function for the simulation of nonlinear internal resistances.
The ratio between power consumption and height of the devices has been significantly increased. The models with 3U of height are capable of consuming DC power of up to 7.2 kW per unit and the 6U models even twice as much.
The front offers a large color TFT touch panel for an intuitive kind of manual operation, such as its’ prolific nowadays with smart phones or tablet computers. In parallel operation of multiple devices, a master-slave bus is used to link multiple units to a bigger system where the actual values are totaled.
Power ratings, voltages, currents
The available voltage range portfolio goes from models with 0...80 V DC up to models with 0...750 V DC. Input currents up to 0...1020 A with only one unit are available. The series offers various power classes amongst the single models which can be extended up to 460 kW in cabinets for a significantly higher total current.
Share bus, parallel connection and two-quadrants operation
The so-called „Share Bus“ is an analogue connection at the rear of the devices and is used to balance current across multiple similar units in parallel connection, such as with loads of this series and series EA-ELR 9000. It can also be used to build a two-quadrants system in connection with power supplies of series EA-PSI 9000 or EA-PS 9000. This system is dedicated for testing purposes using the source-sink principle.
The devices of the EA-EL 9000 B series are equipped with thermal derating in order to avoid overheating when operating in the maximum power range. The lower the ambient temperature and the better the cooling, the higher the power that the load can take. The nominal intake power before the derating starts is defined at 21°C ambient temperature.
Battery test & MPP tracking
For purposes of testing all kinds of batteries, such as for example constant current or constant resistance discharging, the devices offer a battery test mode. This show extra values for elapsed testing time and consumed capacity (Ah). All the data can be recorded directly to USB stick.
For photovoltaics related tests there is another function included as standard: MPP tracking. Four modes allow for simulation of the typical characteristics of solar inverters being connected to solar modules or panels. The function is used to determine typical operation parameters, such as the so-called Maximum Power Point and the related values UMPP, IMPP and PMPP. One of the modes even offers particular analysis with different irradiation values in form of a table with 100 points.
Remote control & connectivity
For remote control, there are by default two interface ports (1x analogue, 1x USB) available on the rear of the devices, which can also be extended by optional, pluggable and retrofitable, digital interface modules (dedicated slot). For the implementation into the LabView IDE we offer ready-to-use components (VIs) to be used with the interface types USB, RS232, GPIB and Ethernet. Other IDEs and interfaces are supported by documentation about the communication protocol.
Windows users can profit from the free software “EA Power Control”. It offers a feature called “Sequencing”, where the device is controlled through a semi-automatic table in CSV format. This table represents a simple test procedure and can be created and edited in MS Excel or other CSV editors and then imported into the software tool. See page 146 for more information.