Shenhai Explosion-Proof
Enhanced-safety electrical equipment must be encased in a properly designed enclosure. This casing is crucial not only for assembling electrical components but also for shielding them from external threats such as solid particles, moisture, and water. These elements pose a serious risk as they can lead to short circuits, insulation breakdowns, and potentially hazardous electrical discharges.
It’s well-known that electrical devices are vulnerable to environmental factors. Solid contaminants, for example, can infiltrate and cause short circuits, while moisture can degrade insulation, leading to leaks and sparks – a dangerous situation indeed. Using enclosures with an appropriate protection rating can prevent these risks.
According to the GB4208-2008 standard, which specifies enclosure protection levels (IP codes), these levels are represented by the IP code followed by two numbers and sometimes additional letters. The first number indicates the level of protection against solid objects, and the second against water. For example, an enclosure rated IP54 offers a certain degree of protection against solids and liquids. GB4208-2008 categorizes protection against solids into 6 levels and against water into 8 levels.
When it comes to enclosures:
With exposed live parts, a minimum of IP54 is required.
With insulated live parts inside, it should also be at least IP54.
| Dust level | Characteristics of solid foreign objects | Characteristics of solid foreign objects |
|---|---|---|
| Brief Description | Meaning | |
| 0 | Unprotected | |
| 1 | Prevent solid foreign objects with a diameter of no less than 50mm | The 50mm spherical test tool with a diameter of must not completely enter the casing |
| 2 | Prevent solid foreign objects with a diameter of no less than 12.5mm | The 12.5mm spherical test tool with a diameter of must not completely enter the casing |
| 3 | Prevent solid foreign objects with a diameter of no less than 2.5mm | The 2.5mm spherical test tool with a diameter of must not completely enter the casing |
| 4 | Prevent solid foreign objects with a diameter of no less than 1.0mm | The 1.0mm spherical test tool with a diameter of must not completely enter the casing |
| 5 | Dust prevention | |
| 6 | Dust density |
| Waterproof grade | Waterproof grade | Waterproof grade |
|---|---|---|
| 0 | No protection | |
| 1 | Prevent vertical water dripping | Vertical dripping should not have harmful effects on electrical equipment |
| 2 | Prevent water dripping in the vertical direction when the shell tilts within a range of 15 ° from the vertical direction | When the vertical surfaces of the casing are tilted within a vertical angle of 15 °, the vertical dripping of water should not have a harmful effect on the electrical equipment |
| 3 | Rain protection | When the vertical surfaces of the casing are tilted within a vertical angle of 60 °, rain should not have a harmful effect on the electrical equipment |
| 4 | Anti splash water | When splashing water in all directions of the casing, it should not have harmful effects on electrical equipment |
| 5 | Water spray prevention | When spraying water in all directions of the casing, it should not have harmful effects on electrical equipment |
| 6 | Anti strong water spray | When spraying strong water in all directions of the casing, the strong water spraying should not have harmful effects on electrical equipment |
| 7 | Prevention of short-term immersion | When the casing is immersed in water at the specified pressure for a specified period of time, the amount of water entering the casing will not reach a harmful level |
| 8 | Prevention of continuous diving | According to the conditions agreed upon by both the manufacturer and the user, the amount of water entering the casing shall not reach a harmful level after continuous submergence into the water |
For venting:
In Class I equipment, a minimum of IP54 (for non-light-emitting live parts) or IP44 (for insulated live parts) is required.
For Class II equipment, the rating should not be less than IP44, regardless of the type of internal components.
If enhanced-safety electrical devices have intrinsically safe circuits or systems, these should be separately arranged from non-intrinsically safe circuits. Non-intrinsically safe circuits must be housed in a compartment with at least an IP30 rating, marked with a warning: “Do not open while powered!”
The enclosure of enhanced-safety electrical equipment is vital for protecting internal components from external interference and ensuring the insulation performance of the circuitry remains intact, hence the term “enhanced-safety enclosure.”