If you need to source a low-temperature variable frequency drive such as -40℃, there are very few options on the market as most off-the-shelf drives only rate to -10℃, with a few rated at -20℃. Minus 40℃ is the low temperature extreme designated by most military electronic standards to achieve “mil-spec” or ruggedized drive rating. Coincidentally, -40℃ and -40℉ are the same temperature and will sometimes be represented as just “-40” without the C or F designation.
Low temperature-rated single and 3-phase drives rated for -40℃ are required for Military and outdoor commercial applications such as rooftop A/C, heaters, generators, oil pumps, etc. The drive must be prepared for extreme low and high temperatures wherever they operate.
The drive also may need to be World Rated because the final installed location may not be known. Militaries must be prepared to operate anywhere in the world. Also, international business and consumer products work and are shipped worldwide.