W21 series Ex e increased safety motors technical parameters：
Protection level: IP55
Insulation level: Class F
Temperature rise level: Class B
Continuous duty: S1
Ambient temperature: 40°C, below 1000 meters above sea level
Remarks: IEC standards: Zone 1 and 2; Group IIB CENELEC standards: Group II; Category 2 and Division 1
Motors running in Zone 1 can also run in Zone 2, because the operating conditions in Zone 1 are more demanding than those in Zone 2. Similarly, Ex e increased safety motors are also applicable to Group IIA, IIB and Category 3