1. Please note that before using the pen, wire, clip connected to form a circuit path.
2. the LED pen of positive and negative, positive tip of the pen, clip ground as a negative, reverse can not be used in the detection circuit.
3. Test circuit used in the voltage range of 6V~24V ( car / motorcycle ) or 36V~72V ( electric vehicles ), the voltage more than 24V or 72V easy to make LED lamp burned or shorten the test pen pen life.
Warning: Do not use needles lead to higher risk of injury factor. so according to their own habits need to change the use of the metal end of the test pen shape.