Several light sources connected in serial or parallel to the same driver

Third document of our technical news serial is focused on other question repeated over the time that  we have to explain it constantly. Clients  ask  for information regarding the use of one constant current driver to feed several light sources.

Remembering last article, our luminaires integrate two components, one driver or converter and one light source. T his configuration it is highly recommended by us and we always indicate the use of our products  following this so we do not recommend  the connection, in serial or parallel, of several light sources in a  single driver or converter.

Above you can see the explanation because of JISO ILUMINACIÓN, SL. does not recommend the connection, in serial or parallel, of several light souces in a single driver or converter.

Parallel Connection

This kind of connection would be the less recommendable so, when we connect several light sources to a single driver or converter, the driver has to be able to feed a current (contantly) equal to the sum of the design currents of the light sources associated.

For example, If we connect 3 light sources designed to work with 300mA, then, the associated driver or converter must be able to supply 900mA.

The problem appears when one light source is not connected properly, or it appears a failure, or any source does not receive the energy correctly, so, in that case, the current, which should be divided equally between light sources, it is divided incorrectly and the other light sources received more current than the one they need.

For example, in the example shown above, if one light source is not switched on it is produced, as a result, an increasement in the current of the others and, in that case, instead of 300mA, each light source will receive 450mA. This can generate an overheat in the light sources and the consequent failure. If one more light source fails then the last one will receive 900mA so in a small period of time it will fail as well.

Serial Connection

This kind of connection, although it is less problematic to the light sources, it  would not be recommendable either. In this case the driver has to be able to supply the design current (constantly) of the light sources and, besides, it has  to be included, in its voltage range, the sum of the voltages of the light sources (the load of each light source).

For example, if we connect 3 light sources which are designed to work with 300mA and 36V, then the associted driver or converter has to be able to supply 300mA and within its voltage range will have to include the sum of the three voltages (108V). For example, a voltage range of 75-120V.

The problem appears when one light source is not connected properly, or it appears a failure, or any source does not receive the energy correctly, so, in that  case, the continuity of the system is broken.

For example, in the example shown above, if the light sources are not switched on, the continuity of the system disappears and, as a result, every single light source is switched off and we never know exactly where the problem is focused so we will have to waste time in order to find out the problem.

Therefore, JISO ILUMINACIÓN, SL. only supply luminaires which integrate one light source and one driver or converter, and we do not recommend the use of any other kind of connection in other to keep the warranty available because  otherwise the warranty will disappear.

Technical Department