To be used the machine better, please observe the following condition: A ambient temperature is situated between-10º C and 40º C; B operational site altitude above sea level does not surpass 1000M. C In the surroun -ding air dust, the acid, the caustic gas or the matter and so on do not surpass the normal content, except in the welding process. D Not suitably in the air with salt to use long time. E The voltage undulation supplied by power is in rated value± 10%. F The operational site wind power is lower than for 1.5m/s. G. Do not work in the rain.