Most storage devices that do not require vision and a brain to read data fall into this category. Electromagnetic data may be stored in either an analog data or digital data format on a variety of media.
Direct Tripwire Alarm - The wire placed across the path is directly connected with the cord, wire or string placed across the particular path. Laser Tripwire Alarm - An invisible laser, typically an infra-red, is used instead of a cord or string.
This answer is mostly based on the United States electrical system, and the answer may vary depending on where you are. The NEC code specifies that a solid copper wire used to connect to a ground rod must be at least either #6 or #8 gauge (depending on the size of your electrical service cable).#6 cable cable will always satisfy the sizing requirement, though in some cases larger is desirable.or the best lightning protection, your grounding wires should not have any sharp bends. This is because lightning is a very high frequency signal, and the wire's impedance increases with frequency. The 0.4 ohm/thousand feet figure is only valid at DC (zero frequency).