3.  Protect disconnected plugs and receptacles with  caps or plastic bags to keep debris from entering and  causing faults. 4.  Do not use excessive force and do not pull on attached  wires. or where complex bends are necessary. Transparent adhesive  tape is recommended when cutting flexible conduit with a  hacksaw to minimize fraying of the braid. This section provides general procedures and safety  precautions for installation of commonly used aircraft  electrical equipment and components. Electrical load limits,  acceptable means of controlling or monitoring electrical  loads, and circuit protection devices are subjects with which  mechanics must be familiar to properly install and maintain  aircraft electrical systems. Conduit is used in aircraft installations for the mechanical  protection of wires and cables. It is available in metallic and  nonmetallic materials and in both rigid and flexible form. When selecting conduit size for a specific cable bundle  application, it is common practice to allow for ease in  maintenance and possible future circuit expansion by  specifying the conduit inner diameter about 25 percent larger  than the maximum diameter of the conductor bundle. The  nominal diameter of a rigid metallic conduit is the outside  diameter. Therefore, to obtain the inside diameter, subtract  twice the tube wall thickness. When installing additional electrical equipment that  consumes electrical power in an aircraft, the total electrical  load must be safely controlled or managed within the rated  limits of the affected components of the aircraft’s power- supply system. Before any aircraft electrical load is increased, the associated  wires, cables, and circuit-protection devices, such as fuses  or circuit breakers, should be checked to determine that the  new electrical load—previous maximum load plus added  load—does not exceed the rated limits of the existing wires,  cables, or protection devices. From the abrasion standpoint, the conductor is vulnerable  at the ends of the conduit. Suitable fittings are affixed to  conduit ends in such a manner that a smooth surface comes in  contact with the conductor within the conduit. When fittings  are not used, the conduit end should be flared to prevent wire  insulation damage. The conduit is supported by clamps along  the conduit run. Many of the common conduit installation problems can be  avoided by proper attention to the following details: The generator or alternator output ratings prescribed by the  manufacturer should be compared with the electrical loads  that can be imposed on the affected generator or alternator  by installed equipment. When the comparison shows that the  probable total connected electrical load can exceed the output  load limits of the generator(s) or alternator(s), the load should  be reduced so that an overload cannot occur. When a storage  battery is part of the electrical power system, ensure that the  battery is continuously charged in flight, except when short  intermittent loads are connected, such as a radio transmitter,  a landing gear motor, or other similar devices that may place  short-time demand loads on the battery. Damaged conduit sections should be repaired to prevent  injury to the wires or wire bundle. The minimum acceptable  tube bend radii for rigid conduit as prescribed by the  manufacturer’s instructions should be carefully followed.  Kinked or wrinkled bends in a rigid conduit are normally  not considered acceptable. Placards are recommended to inform crewmembers of an  aircraft about the combinations of loads that can safely be  connected to the power source. In installations where the ammeter is in the battery lead  and the regulator system limits the maximum current that  the generator or alternator can deliver, a voltmeter can be  installed on the system bus. As long as the ammeter does  not read discharge, except for short intermittent loads such  as operating the gear and flaps, and the voltmeter remains at  system voltage, the generator or alternator is not overloaded. Flexible aluminum conduit is widely available in two types:  bare flexible and rubber-covered conduit. Flexible brass  conduit is normally used instead of flexible aluminum where  it is necessary to minimize radio interference. Flexible  conduit may be used where it is impractical to use rigid  conduit, such as areas that have motion between conduit ends  4-67 Controlling or Monitoring the Electrical Load Electrical Equipment Installation Conduit Electrical Load Limits 1.  Do not locate conduit where it can be used as a  handhold or footstep. 2.  Provide drain holes at the lowest point in a conduit  run. Drilling burrs should be carefully removed from  the drain holes. 3.  Support the conduit to prevent chafing against the  structure and to avoid stressing its end fittings.