Basic Configurations for Gecko Drives Gecko_540B3 configuration for a 3 axis machine with X Y Z axes. To use the charge pump on a G540 your base period must be set to 50,000 or lower. Otherwise disable the charge pump feature. Gecko_540B4 configuration for a 4 axis machine with X Y Z A axes. To use the charge pump on a G540 your base period must be set to 50,000 or lower. Otherwise disable the charge pump feature.