I will use it outdoors: do I need IP45 or IP67?
According to IEC 60529, IP45 (KS250) is protection against solid objects larger than 1 mm and against water spray from any direction; IP67 (PT500) means dust tightness and resistance to temporary immersion up to 1 m. In field applications open to rain, dusty or where water can collect, the IP67 rated PT500 should be preferred.
The two digits of the IP code describe different things. The first digit is protection against solid objects and dust: 4 = objects larger than 1 mm, 6 = dust tight. The second digit is water protection: 4 = water spray from any direction (splashing), 7 = temporary immersion up to 1 metre.
How this maps onto the products:
- KS250 - IP45: Protected against objects larger than 1 mm and against splashing water. Suitable for enclosed spaces, under eaves, inside cabinets or sheltered environments where the dust is not fine.
- PT500 - IP67: Dust tight and resistant to temporary immersion. Suitable for locations directly exposed to rain, dusty field sites, agriculture and outdoor automation.
Two important warnings: IP67 does not mean continuous underwater use; furthermore, pressurised jet washing is a separate test defined by IPX9K and IP67 does not cover it. For the ST42 no IP rating is stated in the product data; for this reason no commitment can be given regarding its resistance to outdoor conditions, and since there is no IP data it is not recommended for outdoor use.
During installation, take care that the cable entries are at least as sealed as the enclosure; the weakest link is usually the gland or the bushing.
The full topic: DC Motor Driver Selection Guide