Quality, our best argument

All of our products undergo thorough quality control procedures, which serve to endow our product with significant added value. ELT personnel are wholly dedicated to this task.

Electronic ballasts, ignitors, drivers, modules and strips for LED are subject to different tests and trials at several phases in the production process. We always work by area, with materials and implements that are protected against Electrostatic Discharge (ESD). All personnel working in the electronic section must use the appropriate equipment, including suitable clothing and special heel pads.

The process begins with the design of the new electronic models. Our I+D+i (Research, Development and Innovation) Department is always on the look out for the best components for its designs, which are then certified by the Quality Department by means of different trials, using both environmental chambers, and operational and destructive tests. Therefore, we are fully assured that the components chosen and the design are suited to the quality level we wish to and must maintain.

Whenever a design is ready a pre-series is then made. These new products are tested by the Quality Department. Endurance tests are done in humid conditions, at low and high temperatures, introducing all types of loads and different manufacturers, in addition to the safety and operating tests stipulated by the applicable regulation. When all of the tests have been successfully passed, the model is then approved for manufacturing.

Whenever raw materials are received, endurance, measurement and operation tests are carried out to ensure that the materials in question meet the highest quality specifications that ELT demands of its suppliers.

When production begins, conventional, SMD, and special components are fitted onto the PCB by automated machines. At each point, ELT operators check that the components fitted are correct for the production in progress. To this end, a computer system with measurement software indicates to the operator which component must be fitted and where, in accordance with bar codes. A component cannot be fitted in the wrong place. If there is a mistake, the production line will stop until the operator addresses the problem. In addition, the system registers the batch to which the component belongs and where and when it was fitted, thus enabling us to trace the components used at any given moment. Every time a certain number of PCBs comes out of the machine, the person in charge of the assembly line must measure all components with an LCR meter, checking them against a sample provided by Quality personnel.

After all the SMD components have been fitted, the circuit goes through an Automated Optical Inspection (AOI) machine, which checks that all the components have been properly fitted to the PCB and that the value indicated on them is the right one, reading the numbering marked by the manufacturer. For reflow system production it also checks whether or not these have been properly soldered. The optical machine uses a cone with differently coloured LEDs (red, green and blue) and a high resolution camera at its highest point. In a fraction of a second, the AOI system gathers together millions of data points (pixels) and compares them with a database that a technician has previously programmed with the acceptance criteria (PCB components, the value marked on them, the soldering, the angle and whether or not they are in the right place, without deviations).

If the optical system detects an error, it automatically discards the board on to a belt attached to the machine and indicates the position and type of fault to be corrected.

The PCBs then pass through the wave soldering process on the bottom face, in a nitrogen environment process, with all oxygen removed to avoid oxidation and the generation of impurities, thus enhancing the quality and uniformity of the process. Furthermore, and with great care, operators visually inspect the soldering for defects, for unsoldered components, raised components, short circuits, open circuits, etc.

Thereafter, the PCBs are passed through a machine called a Manufacturing Defects Analyzer (MDA) or Test In Circuit (TIC). By means of a bed of nails tester that electrically brings into contact the test points and the data acquisition cards, this station checks that all the electronic components that go to make up the product have been properly soldered and that their electric value is right, all of which is done to previously programmed tolerances (less than 0.5%). If a fault is detected, the product is automatically separated and the computer system indicates the type of fault, its position and value, so that the machine operator can solve the problem.

When equipment is passed, it automatically goes on to the following test station. The “Operational Test” electrically connects all of the apparatus. This is a real test, with fluorescent tubes, metal halide lamps, receiving the load required by each model. A series of electrical parameters are measured, both on the mains as well as at intermediate PCB test points. Some of these measurements are, for example, mains voltage, power factor, lamp current, lamp wattage, and a long list of other parameters that tell us at this point in the production process whether or not the product is correct and 100% operational. If the product did not pass the test, it would be sent to Quality in order to locate the problem and come up with a solution to avoid any repeat of the fault.

After this phase, the product moves on to the finishing area where, by means of automated machines it is fitted with input materials such as, circuits, bases and metal covers, polyester film for insulation and, where applicable, clips and conductive thermal grease.

The equipment is automatically assembled without the need for human intervention. After it has been fitted into its enclosure or casing, and without leaving the production line, the tests stipulated by safety, dielectric strength and continuity to ground regulations are carried out. Thereafter another operational test is done to check that the electrical values are still correct. If everything is in order, the production batch is identified by laser marking (indicating the time and date of manufacture). Whatever the case, operators sample the product on a bench with calibrated measurement devices, checking that the equipment turns on properly, locks in the absence of electric charge and falls within the set parameters.

The product is now 100% adequate, but in our case, we subject it to yet another test. All ballasts, transformers, drivers, ignitors, etc., undergo the Burn-In test. They are checked under abnormal conditions with high temperatures for an hour or more (as deemed appropriate by the Quality Department) to eliminate the premature failure involved in the use of electronic components. After this test, we at ELT believe the manufactured product to meet our client’s expectations, both with respect to us, as well as regarding our products. The product is then packaged and stored under ideal humidity and temperature conditions to await dispatch to the client.

All of these trials and tests provide a clear insight into our product and production system, enabling us to detect possible weaknesses, to remedy them and to develop our designs and production.