PDF Publication Title:
Text from PDF Page: 506
AC 43.13-1B CHG 1 or components. Use of a circuit breaker as a switch is not recommended. Use of a circuit breaker as a switch will decrease the life of the circuit breaker. 11-52. CIRCUIT BREAKER MAINTE- NANCE. Circuit breakers should be periodi- cally cycled with no load to enhance contact performance by cleaning contaminants from the contact surfaces. 11-53. SWITCHES. In all circuits where a switch malfunction can be hazardous, a switch specifically designed for aircraft service should be used. These switches are of rugged con- struction and have sufficient contact capacity to break, make, and continuously carry the connected load current. The position of the switch should be checked with an electrical meter. a. Electrical Switch Inspection. Special attention should be given to electrical circuit switches, especially the spring-loaded type, during the course of normal airworthiness in- spection. An internal failure of the spring- loaded type may allow the switch to remain closed even though the toggle or button returns to the “off” position. During inspection, at- tention should also be given to the possibility that improper switch substitution may have been made. (1) With the power off suspect aircraft electrical switches should be checked in the ON position for opens (high resistance) and in The OFF position for shorts (low resistance), with an ohmmeter. (2) Any abnormal side to side move- ment of the switch should be an alert to immi- nent failure even if the switch tested was shown to be acceptable with an ohmmeter. 9/27/01 Switches have electrical contacts and various types of switch actuators (i.e., toggle, plunger, push-button, knob, rocker). (1) Contacts designed for high-level loads must not be subsequently used for low- level applications, unless testing has been per- formed to establish this capability. (2) Switches are specifically selected based on the design for the aircraft service cur- rent ratings for lamp loads, inductive loads, and motor loads and must be replaced with identical make and model switches. c. Proximity Switches. These switches are usually solid-state devices that detect the presence of a predetermined target without physical contact and are usually rated 0.5 amps or less. d. Switch Rating. The nominal current rating of the conventional aircraft switch is usually stamped on the switch housing and represents the continuous current rating with the contacts closed. Switches should be der- ated from their nominal current rating for the following types of circuits: (1) Circuits containing incandescent lamps can draw an initial current that is 15 times greater than the continuous current. Contact burning or welding may occur when the switch is closed. (2) Inductive circuits have magnetic en- ergy stored in solenoid or relay coils that is released when the control switch is opened and may appear as an arc. (3) Direct-current motors will draw several times their rated current during start- ing, and magnetic energy stored in their b. Electromechanical Switches. Page 11-16 Par 11-51PDF Image | AFS-640
PDF Search Title:
AFS-640Original File Name Searched:
ac_43.13-1b_w-chg1.pdfDIY PDF Search: Google It | Yahoo | Bing
5,000 BF Shipping Container Lumber Dry Kiln For Quality Lumber The 5,000 BF container kiln consists of one 40 foot high-cube aluminum shipping container... More Info
Shipping Container Lumber Dry Kilns by Global Energy Global Energy designed and developed the container kiln back in 1991. The purpose is to give access to portable sawmill owners, furniture makers, and small business the value added profit of dry kiln lumber and quality hardwoods... More Info
Vacuum Kiln Conversion Kit for Lumber and Wood Dry Kilns Convert your existing conventional dry kiln into a fast drying vacuum kiln. Similar to vacuum bagging in the boat building and aircraft industry, we have come up with a proprietary process which allows you to build a very simple vacuum kiln at a fraction of the price, and without the intensive conventional metal chamber structure... More Info
Vacuum Pump Cart System for Bagging Clamping Wood Drying and more Vacuum Cart with 2HP Pump and Dual Pistons with multiple multiplex vacuum ports and liquid reservoir... More Info
Vacuum Bagging Basics Vacuum bagging is a method of clamping, which has traditionally been used in the composites industry, but can also be used for vacuum drying materials, including wood products... More Info
| CONTACT TEL: 608-238-6001 Email: greg@globalmicroturbine.com | RSS | AMP |