In this article, we will discuss the NEMA 12 electrical enclosure and its features for indoor uses. NEMA 12 electronics enclosure is primarily built to be used in relatively mild environments. However, this one is a sealed enclosure that does not allow natural ventilation coming from the outside and therefore it needs an additional cooling system to keep the insides of the enclosure to reach temperature below the thermal requirements of the equipment housed inside.
Characteristics for Indoor Use
The NEMA 12 electronics enclosure is specifically designed for indoor use only and it is not advisable to be used for outdoor applications – especially when there are harsh elements such as wind, rain and snow. NEMA 12 enclosures are usually manufactured from painted steel for the additional strength and rigidity for the electrical box. However, plastic and fiberglass are also used to manufacture NEMA 12 but the strength and physical characteristics should comply with the right specifications.
It Sealed, Non-Ventilated
Like with what we mentioned earlier, the NEMA 12 enclosures are sealed and does not have a very good internal ventilation. The degree of sealing of NEMA 12 enclosures are tightly sealed and it is very essential to give the enclosure a cooling system to properly manage the equipment inside the enclosure to avoid heat load. Sometimes the use of the filtered fans is questionable because it can ruin the integrity of the enclosure’s rating. There are alternative cooling methods manufacturers can use to achieve the NEMA 12 rating. There are closed-loop systems like air conditioning and air to air heat exchangers.
Circulating Dust
The electrical box gives protection for the equipment against circulating dust that are commonly found in companies or factories that as very dusty materials. This dust includes fibers, flyings, or lints. The company should note that the level of protection NEMA 12 gives does not include protection from wind borne dust and for environments that has this condition, a NEMA 4 should be an option.
Protection from Falling Dirt
This characteristic is very similar to that circulating dusts – but this one is primarily intended to describe the atmospheric dirt which falls vertically and not roaming around horizontally.
Protection from Dripping of Non-Corrosive Liquids
The electronics enclosure should be able to give an enough protection against dripping liquids. Usually, this characteristic should be able to include very minor water leaks, dripping water from steam traps, and oil leakage from heavy machinery. Since the liquid requirement is that it should not be non-corrosive, special corrosion protection is not needed anymore.