g code reset

i can use 840d powerline with 3 axis vmc machine. when i on the machine on all g code screen 8= g 500 is on by defult when i run g54.....g56 is change 8=g54....g56 but when i power off then on the machine the 8=g 500 i want change this logic so how is possible alway on a last g54....g56 by defaut in 8 number of g code sereen .

change channel parameter 20150 tab 7 to " 2"

1 represent G500

2 represent G54

3 represent G55