Think green for the sake of the environment

Paul Boughton

Testing of power supplies, energy storage or electronic components for function, performance and parameters is generally done using electronic loads. During testing voltage, current, resistance and output can be set and controlled for the sake of a reproducible process.
The commonly used electronic loads generate and control the required current via semi-conductors which is converted to heat, needing a complex cooling process.

The surrounding room thus requires air conditioning leading to high cost /energy, maintenance, equipment costs. The electronic loads in the series ELR 9000 from EA Elektro-Automatik lead to substantial reduction. Up to 95 per cent of the DC power required for testing is converted and redirected back to the grid and little heat is generated. Expensive conditioning units are no longer required, high energy costs eliminated (evironmental balance)
This can be shown in a typical application, where a 48V DC telecom power supply  is to be burn-in tested. The 3kW unit set to 56V output voltage is tested for 2 hours at 53,5A. In an 8 hour day total usage is 24 kWh. Using the load with power feed back at least 90% of this power will be redirected.
Test costs with conventional load   24kWhx0.25€ = 6,00€/Tag = 1.320,00€/Year
Test costs with power feedback load 2.4kWh x 0.25€ = 0.60€/Tag = 132,00€/ Year
(2.4 kW resulting from a 90 per cent feedback)  

Annual saving 1.320,00 € - 132,00 € = 1.188,00 €

This high saving rate generates a fast pay back for a power feedback load compared to a conventional load.

Flexible input, extensive functionality and fittings

The feedback loads have a modular concept satisfying a wide spectrum of usage for up to 1500VDC, up to 510A and from 3.5 kW up to 150kW and even beyond, owingd to the master-slave bus feature. The performance of the loads allows dynamic load profiles for applications such as testing of photovoltaic modules.

New operating concept

The calculation program and function generator are intuitively operated in a large graphic-display and touch- screen HMI to make adjustments quickly and easily. It displays the set and actual values (U,I,P,R) as well as   many other conditions at the same time. The function generator includes curves such as sine, triangle, rectangle, pulsing mode and others.

Communication is paramount

The communication unit contains a USB connection, analog interface and master-slave port, through with the e-loads may be operated and monitored remotely without additional options. Owing to the plug’n play slot, interface options such as RS232, Ethernet, Profibus, Profinet, Devicenet or CANbus can be retrofitted by the user.  
ELR 9000 loads allow makers of power supplies and energy-storage systems to improve environmental balance and reduce substantial costs. Whether laboratory or industrial power supplies, energy storage devices (eg Li-batteries, capacitors, fuel cells, etc) can use these new loads. They are even suitable for testing hybrid vehicles using eg battery packs of hundreds of volts.