The Hash Academy

AIRCRAFT ZONING AND ELECTRICAL SAFETY General   For work on the electrical system it is necessary: - to know and obey the standard safety practices - to have a good knowledge of the electrical standard practices - to have a good knowledge of requirements (processes, WARNINGS, CAUTIONS etc.) before you start the work.  This is necessary to prevent injury to persons and/or damage to equipment. Electrical Safety Practices  Before you start work, open, safety and tag the circuit breaker(s) related to the system/equipment to prevent the supply of electrical power to the system/equipment during the maintenance work. This prevents the risk of: - Electric shocks that can occur if you touch energized wiring connections, terminals, etc. - Short circuits that can occur if metal tools or parts accidentally touch energized wiring, terminals, contacts, etc.   Some circuit breakers (A320 family only) have a red threaded bush. This bush prevents reset of the circuit breaker in flight (the crew cann

 Wire Identification  There are two families of wire types:  A. United States (US) : The United States (US) wire types are installed on A300/A310/A300-600. Their core diameter has US diameters. For example AKA gauge 24 has 19 strands diameter 0.127 mm (0.01 in.).  B. Metric (M) Types: The Metric (M) wire types are installed on the other Airbus A/C for weight saving. For example CF gauge 24 has 19 strands diameter 0.12 mm (0.0050 in.). P/N Identification    All the wire types (US and Metric) agree with Standards (ABS, ASNE, EN, NSA,...). The wires are identified as follows: Standard P/N  -  Wire type code - Wire gauge  ABSXXXX - XX - XX EXXXX - XX -  XX NSAXXXXXX -  XX -  XX     For EN Part Numbers: Standard P/N - Code letter for number of cores - Wire gauge code - Insulation color code  ENXXXX - XXX  X  XXX X If it is necessary to replace between US and metric types of wires on the aircraft  you can use an interchangeable Metric wire given in ESPM chapter 20-32-21. the standard part nu

 Electrical Standard Practices Manual (ESPM) Introduction to ESPM: The Electrical Standard Practices Manual (ESPM) gives descriptive data and procedures for the electrical installations on all aircraft of the AIRBUS family. The standard practices information in this manual tells you how to do maintenance for the continued airworthiness of the aircraft. The ESPM is part of the Instructions for Continued Airworthiness (ICA). The ESPM always gives the best practices to do the installations or the repairs. There are several chapter 20, depending on the vendor responsible for the system (ECE, Honeywell, etc.) but whatever the vendor, their chapter 20 follows the same layout. The data contained in the ESPM includes:  - Description of electrical items. - Removal/Installation of electrical items. - Electrical checks. - Repair procedures. - Damage assessment procedures. - Other procedures as necessary (Cleaning, Inspection/Check, etc.).  The Electrical Standard Practices data related to Pow

CRIMPING Crimping ensures electrical and mechanical connection of the wire to an item of equipment or to a connecting system by means of the end fitting. Crimping Tools Special crimping tools are needed to crimp a connecting device onto a wire. A properly crimped terminal provides a joint between the wire and the terminal as strong as the wire itself. The preferred crimping tool is a ratchet-type crimper that is periodically calibrated to ensure a consistent and proper crimp. When using a ratchet-type crimping tool, the handles of the tool will not release until the jaws have moved close enough together to properly compress the terminal barrel. Many crimping tool manufacturers are available (AMP, Buchanan, Burndy, Cannon, Daniels, Hughes, Raychem, etc.), who provide different types of crimping tools to be used with different types of connecting devices. Some have fixed locators, and the tools come in different sizes indicated by the color coding on the handle. Some tools have removable