NT-320 Contact-Type Digital Voltage Tester FAQ and support
Is it possible to conduct a contactless electricity test?
Contact-free electricity test is suitable for a single live wire.
Live: display--U buzzer sounds;
Not charged: display --- the buzzer does not sound;
Shielded wires, two-core, three-core or multi-core composite wires will interfere with each other and cannot be measured.
Why can’t the NT-320 be inserted into some three-prong outlets while other brands can?
The NT-320 is designed to comply with applicable national standards, which specify the width and thickness of the voltage tester tip. As a result, it may not fit certain outlet designs or dimensions.