BASIC MEASUREMENTS

1-18 · Periodically clean all strap-and-clamp connectors to ensure that all direct metal-to-metal contacts are free from foreign matter. · Check all mounting hardware for mechanical failure or loose connections. · Replace any faulty, rusted, or otherwise unfit grounding strap, clamp, connection, or component between the equipment and the ground to the ship’s hull. · When replacing a part of the ground connection, make certain that the metallic contact surfaces are clean and that electrical continuity is re-established. · After completing the foregoing steps, recheck to be sure that the connection is securely fastened with the correct mounting hardware. Paint the ground strap and hardware in accordance with current procedures. Because of the electrical shock hazards that could be encountered aboard ship, plugs and convenience outlets for use with portable equipment and power tools normally are standard three-prong type. Both plugs and outlets are keyed so that the plug must be in the correct position before it can be inserted into the receptacle. To ensure that the safety factors incorporated in these devices are in serviceable condition and are safe for use, you must perform the following precautions and inspections: · Inspect the pins of the plug to see that they are firmly in place and are not bent or damaged. · Check the wiring terminals and connections of the plug. Loose connections and frayed wires on the plug surface must be corrected and any foreign matter removed before the plug is inserted into the receptacle. · Use a meter to ensure that the ground pin has a resistance of less than 1 ohm equipment ground. · Do not attempt to insert a grounded-type plug into a grounded receptacle without first aligning the plug properly. CAUTION Never use a power tool or a piece of portable test equipment unless you are absolutely sure that it is equipped with a properly grounded conductor. BASIC MEASUREMENTS Electronic measurements involve the fundamental electrical quantities of voltage and current and the inherent characteristics of resistance, capacitance, and inductance. In circuits being tested, voltage and current are dependent upon resistance, capacitance, and inductance for their distribution; therefore, voltage and current measurements are valuable aids in determining circuit component conditions and in the evaluation of symptoms. Practically any reading obtained from the use of test equipment will depend on these basic measured quantities of resistance, capacitance, and inductance.