The new EL 9000 B range is flexibly applicable. The electronic loads may, by virtue of the modular system, be combined into one device with a power of 14,400W or into a cabinet system of up to 72kW. Problems with oscillation or high frequency input voltages are overcome.
While electronic loads are used for a variety of testing of power supplies, batteries or fuel cells, they should be multi usable. EA Elektro-Automatik has recognized this need and developed a new series of electronic loads which possess multiple voltage, current and power stages for different applications: the EL 9000 B range. Power from 300W up to 72kW, voltage from 80V up to 750V and current up to 5100A are offered.
Individually customisable power
The modular system allows power parts with 600W, 1200W and 2400W to be combined at will in one unit with a power of up to 14400W. For power levels of up to 72kW a master device with slave devices are built into a single unit in a cabinet. The resulting system enjoys the same user comfort and functionality as the individual units.
Interfaces: integrated and extendable
To control and monitor the units they are fitted with a communication unit which performs as an exchange between the HMI, power unit and the outside world. As standard the units are fitted on the rear side with an analogue and USB port. All ports are galvanically isolated. A Plug & Play slot allows other interfaces for Ethernet, Modbus, TCP, Profinet, Profibus, CANopen, CAN and RS232 to be installed.
FPGA based parallel signal processing
The digital regulation and control used in the EL 9000 B series electronic loads are based on a 16 Bit AD/DA converter principle. Because of the parallel signal processing of the FPGA the elapsed time of a signal - measurement, calculation and adjustment - is less than 1µs. Thus, a band width of 1 MHz can process current, voltage, power and resistance simultaneously. The user allotted look up tables (LUTs) also work with a band width of 1MHz. Thus complex, non-linear resistance characteristic curves, such as in LED chains or PV rectifiers, can be simulated. The table values can be generated in CSV or text format and transferred to the look-up tables via USB.
New standard: EL with extended functionality
A notable feature is the FPGA based digital function and arbitrary curve generator which enables a time based, freely programmable load profile. Hence multiple progressions such as sine, triangle or square curves can be generated. Additionally, there is a sequencing and logging function for selection and recording data and a battery management system. Other constants such as limit values for voltage, current, power and resistance, as well as time based parameters are configurable. A high definition TFT touch panel enables intuitive operation. The menu is multilingual.
Active damping, reduced capacity
EA have achieved with the new series the elimination of the deficits commonly found in electronic loads: control oscillation, voltage shift or high frequency input voltage. The EL 9000 B series secures a high current stability by using an active electronic damping of the DC input circuit. In this way, the capacity of the DC input filter is minimised and the current source protected. In addition, the loads are insulated from input circuit to chassis, operating controls and the analogue and digital interfaces. This double insulation secures a permitted floating voltage of +/- 400V. Thus, all equipment connected via the interface ports are protected against high tension.
Intelligent heat management protects against test termination
An important point is thermal protection. If components in the unit exceed a certain temperature, then commonly the input is switched off. The switching off plus the temperature delta between off and on temperature result in the load being unable to take power for a time. This results in elaborate tests being often terminated. To avoid this the new EL 9000 B loads are fitted with an intelligent heat management.
With the ELM 5000 series EA Elektro-Automatik has developed a new range of programmable electronic DC loads with energy recovery. The ‘M’ in the product name stands for the modularity of the series: up to 10 modules may be combined in a 19” cabinet with 6 HE.
Up to 94% of the absorbed power is fed back by the system into the supply net. Thus DC sources such as power supplies, solar modules, batteries and other energy storage media can be tested in an environmentally friendly way together with power saving in function and burn-in tests. The user can choose between two models: the electronic load ELM 5080-25 with 80V, 25A and 320W or the load ELM 5200-12 with 200V, 12A and 320W. To increase performance loads can be switched in parallel. The system is flexible: the chassis can be populated with different modules. Control and monitoring of the equipment is enabled via an Ethernet port. Furthermore, load processes can be loaded or logged via a USB stick. Thus tests may be simply programmed and recorded.
Intuitive operation using a TFT touch panel
The devices are operated using the high definition colour TFT touch panel of the HMI, intuitively and in multiple languages. The display shows concurrently actual values for voltage, current and power. Moreover the user has a view of set values, the control mode, alarms and warnings together with the input status.
With the EL 9000 DT and EL 9000 T series EA presents electronic loads as desk-top devices, either top or desk-top. These achieve power of between 300W and 1200W, voltage from 80V to 750V and current of 60A. An active electronic damping of the DC input circuit maintains a high level of current stability.
The desk top models of the EL 9000 DT and T series are controlled and monitored via Ethernet, USB and analogue ports. The T models are fitted as standard with a USB port and may be optionally extended with Ethernet and analogue ports via a plug & play slot. All ports and the HMI are galvanically isolated from the input. The devices may be intuitively operated using a high definition TFT display with capacitance touchscreen. The menu is multilingual.
Extensive field of usage
The desk-top loads offer extensive functionality such as function and arbitrary generators and a battery management system so that different batteries and energy storage media can be tested without problem. Furthermore, parameters such as discharge mode and time and shut down criteria can be pre-set. A MPPT function for testing solar panels is also included. Moreover, programmed processes can be loaded from a USB stick and test data recorded.
In order to achieve a high level of current stability the loads are equipped with active electronic damping of the DC input circuit. Undesirable oscillation tendency which may be caused by unknown impedance of the supply source or long connection cables is thereby prevented.
With the new electronic load EL 9000 B 2Q, EA have extended their laboratory power supplies to a two-quadrant operation. The result is a higher application capability. For example, the freed-up energy by braking of a motor, various batteries and other energy storage can be tested or their mode of operation simulated.
The loads in the EL 9000 B 2Q are modular. The user can readily extend the load or fit to requirements. They have the availability of power up to 2400W voltage up to 750V and current up to 170A. Thus the voltage and current of the electronic loads are matched to those of the laboratory power supply series from EA such that these can be combined and expanded to a two-quadrant operation. In this way many more applications can be covered, e.g. the collection of energy released by a motor braking procedure. In addition batteries and other energy storage media can be tested or their function simulated.
Active electronic damping
The loads are equipped with an active damping of the DC input circuit thus guaranteeing a high current stability. Undesirable oscillation tendency is thereby prevented. On the front face the loads may be switched on or off via the HMI which shows the status of the unit. The devices are also fitted with USB ports on the front and rear faces. The ports together with the HMI are galvanically separated. Furthermore, the loads may be parametrised via the USB port allowing current, voltage and power to be adjusted.
Power supply on the laboratory bench demands a clean output current and voltage. The new desk-top devices in the PSI 9000 DT and PSI 9000 T series score with minimal ripple and a small interference spectrum. Furthermore, they offer all the functionality that users expect from a modern laboratory power supply.
Wherever a 19” cabinet would be over dimensioned or take too much space, customers look for a smaller table-top, whether in university laboratories or in limited space availability in research and production. Hence laboratory supply units in the desk-top version need better filters and shielded housings to guarantee clean output voltage and current. Therefore, a power supply with a minimal ripple and small interference spectrum is necessary. In addition, high levels of stability and accuracy are indispensable.
The new DC desk-top laboratory power supplies in the PSI 9000 T and DT series are therefore equipped with the newest switching topology and an improved filter concept: an additional output filter improves the quality of the output voltage. A laboratory power supply with a power output of 1500W, an output voltage of 80V and an output current of 60A has a ripple of less than 1mV. Excellent values are obtained in other power classes as well. Additionally, the complete construction is so chosen as to provide interference well under the levels of EN 55022 Class B. Regarding the electromagnetic compatibility (EMV), the devices fulfil all the required values for interference and immunity from EN 61326. The desk-top power supplies are easy to use and are fitted with the necessary interfaces to connect with a variety of computer systems.
Desk-tops as space saving and economic alternatives
These desk-tops possess all the functions that one expects from EA’s innovative laboratory power supplies. In cramped laboratory environments where usually several devices of differing current and voltage classes would be found, the multiple use desk-tops offer a space saving and economic alternative. The PSI 9000 T and DT have available power of 320W up to 1500W, voltage of 40V up to 750V and current up to 60A. The Desk-top housings of the PSI 9000 DT series are fitted with a support and can also be optionally delivered with a 19” adapter. The PSI 9000 T range scores with its slender forma and can be readily incorporated into a laboratory bench. Thus every user can have the exact power supply in the optimum format.
The PSI 9000 series sets new standards in laboratory power supply: its modular system enables supplies with a power of up to 90 kW to be achieved with only a few modules. A Master-Slave interface and a Shared Bus allow multiple units to be coupled to provide a total system of up to 300kW.
EA Elektro-Automatik has developed a new series of controllable laboratory power supplies which is so versatile that practically any application can be covered. The basis for this is a flexible output stage developed by EA. This enables a significantly larger operational area as the scalability can achieve a much larger voltage and current window enabling one unit to supply a variety of applications – a space and cost saving solution for limited laboratory facilities.
Numerous voltage and current classes
The performance laboratory power supplies in the PSI 9000 range achieve power of 640W up to 90kW, voltage of 40V up to 1500V and current of up to 3060A. Despite this multiplicity the supplies require only a few performance modules. The manufacturer has attained this with a specially developed modular system: components with 640W, 1.5kW and 5kW can be combined in one unit up to 15kW. Thanks to an intelligent Master-Slave interface and a Shared Bus these units can be combined to give a total system of up to 300kW. The system is controlled and selected by a master device with a HMI unit. The slave extension units require no control panel and no further interfaces, thus reducing the total system cost.
In addition to an ordinary laboratory power supply the PSI 9000 series is equipped with a functional and arbitrary generator as well as an automobile start up curve to DIN 40839. Thus, sine, triangular, square and other curve forms can be engaged by keystroke and readily programmed. Furthermore, a sequencing and logging function, a battery management system and the simulation of photovoltaic and fuel cells can be incorporated into the power supply. Many other parameters such as time and limit values for voltage, current, power and resistance are freely configurable.
Because of the multiplicity of functions the developers have introduced a new, user-friendly operating concept: with the aid of a high definition TFT display with a capacitance touch screen the units can be intuitively operated. The menu is clearly designed and available in German, English, Chinese and Russian. With few key strokes the parameters can be selected and values entered via encoder or number panel.
Simulation of non-linear characteristic curves
The digital regulation and control is based on a 16 Bit AD/DA converter. Because of the parallel signal processing of the FPGA the elapsed time of a signal - measurement, calculation and adjustment - is less than 1µs. Thus, a band width of 1 MHz can process current, voltage, power and resistance simultaneously. The user allotted look up tables (LUTs) also work with a band width of 1MHz. In this way, alongside standard linear control, complex non-linear characteristic curves can be simulated, such as those of a battery, fuel cell or a photovoltaic facility. The required tables can be generated in Excel or Text and transferred to the LUTs via USB.
Electronic load with energy recovery
5000-15000 W / 19"-chassis, 3U
USB, Analogue, etc. / TFT Touch panel
Bi-directional laboratory power supply
5000-15000 W / 19"chassis
USB, Analogue, etc. / TFT Touch panel
Laboratory power supplies
320 - 1.500W / Desktop housing
USB/Analogue/LAN / TFT Touch panel
Laboratory power supplies
320 - 1.500 W / Tower housing
USB, Ethernet, Analogue/TFT Touch panel