... working system(S1) is applied Methods of Cooling: 1, Totally enclosed, Self-cooling . IP44,IC410 2, Drip-proof, force ventilated ... 3, Drip-proof, single pipe ventilated. IP23S. IC17 4, Totally enclosed, Double pipes ventilated. IP44. IC37 5, Drip-proof, self- ... ventilated. IP23S. IC01 6, Totally enclosed,force ventilated with air-to water heat exchanger. IP44. ICW37A86 ...