... sensor ring, THC would send out collision signal and lift torch up until no collision exist.4, ... will be showed by the indicator.5, Sensitive and Accuracy is increased 100%.6, CHC300 uses programmable ... Low Level, and limit/auto signal can be normally open or closed, without any change on circuit, and still with ... motor starts with low voltage(better below 2v). And it will not use sensor ring, but needs ...