As per catalog GV2ME - Ambient temperature shown as "Operation - Open mounted -> -20 ... +60 deg C & Operation - In Enclosure -> -20 ... +40 deg C". Do we have to de-rate for +50 in enclosure?
Our GV2 and GV3 thermal-magnetic circuit breaker have a temperature compensation system. This system allows retaining the thermal tripping level when the ambient temperature is from -20° to 60°C in open space and from -20°C to +40°C within an enclosure.
As per the information provided in catalog 60°C for GV2, GV3 mounted in open space is not a problem as well as 40°C for GV2, GV3 installed inside the enclosure is not a problem. If you use GV2 or GV2ME inside the enclosure you have to derate by 1% in respect of each 1°C increment above temperature 40°C and maximum up to 50°C. Likewise derating for open space means 1% for each 1°C increment above temperature 60°C and maximum up to 70°C.
In any case you can not go with the temperature above 70°C for open mounted and 50°C in enclosure mounted.