Why You Shouldn’t Use Fan-cooled Power Supplies in LED Signs

LED Sign Panel

Fan-cooled power supplies may be prone to failure if used in outdoor LED signage.

It is quite common to see a fan-cooled power supply used in imported LED sign panels and in many cases a MEAN WELL power supply has been used.

The manufacturer has most likely selected MEAN WELL because of their reputation for reliability. However, in many cases we see the wrong type of power supply used.

Fan-cooled power supplies draw in air to cool the vital electronic components. If this air is cool and damp, as it often can be outside, then condensation can quickly form inside the power supply. This could potentially lead to a failure, which would not be covered by the warranty.

MEAN WELL has recently launched a brand-new series of ultra slim fan-less power supplies, which are ideal for LED signage applications.

The new MEAN WELL UHP series power supplies remain cool by conducting heat away through the metal housing of the LED sign panel. The minimum surface area required for adequate convection is stipulated in the data sheet.


By using a MEAN WELL UHP series power supply, LED sign manufacturers significantly reduce the likelihood of a failure being caused through moisture ingress.

The most commonly used power supply used in imported LED signs appears to be the MEAN WELL RSP-320-5.

Unfortunately, it is not always possible to retrofit a UHP series power supply as the sign manufacturer may have not designed the panel with enough surface area in the design to dissipate heat way from the power supply.

If you find yourself in this situation ADM can help.

We carry stock of the MEAN WELL RSP-320-5CC, which has had a conformal coating applied during the manufacturing process. This helps reduce the potential of failure from moisture ingress. However, it should be stated that this is not a fool-proof solution.


If you are experiencing problems with the power supplies in your LED signs call ADM today on 1300 236 467. A member of our expert team will gladly discuss your situation and suggest any appropriate solutions you could consider.

Mean Well LOGO

10 April 2018