(b)
Hold discharger in place and tighten setscrew.
(c)
Check security of discharger on mounting base.
(d)
Use these precautions for possible fuel vapors when you use a megohmeter:
WARNING: USE THE PRECAUTIONS THAT FOLLOW WHEN YOU USE A MEGOHMMETER. IF YOU DO NOT USE PRECAUTIONS, THEN IT IS POSSIBLE THAT AN EXPLOSION OR FIRE CAN OCCUR.
1) Use the Quadtech 1863 megohmmeter or equivalent meter with a 500 VDC test voltage and a maximum 5 milliampeter short circuit current. 2) Do not use a megohmmeter at these locations: a) Area adjacent to or below a wing fuel tank vent, five foot (1.524 meters) diameter column, from vent to ground. b) Zero to 18 inches (457 mm) above the ground in the area around the airplane.
3) Make sure that: a) Area is well ventilated. b) Metal workstands are grounded. c) Megohmmeter is plugged into a grounded receptacle. d) Megohmmeter is insulated from metal work stands.
(e) Measure resistance between the end of discharger tip and the discharge base using a megohmmeter of at least 500 volts. To make a good surface contact with the end of the discharger tip, wet a paper towel, cotton cloth or sponge with tap water and place in contact with entire surface of end of discharger tip. Place megohmmeter leads on base and on wet material at end of tip. If reading is high, verify that the wet material is adhering to the meter lead and to the end of the discharger tip. Add more water if necessary and measure again. Take lowest reading. Check that measured resistance is within a reading of 6-100 megohms for tip and trailing edge dischargers.
(10) Refinish bared surface of airplane to match surrounding area.
NOTE: Do not paint any part of dischargers or retainers.
C. Put the airplane back to its usual condition
(1) Put the hydraulic systems for the flight control surfaces back to the usual condition (Ref 27-11-0 MP, 27-21-0 MP, 27-31-0 MP).
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DECOUPLED STATIC DISCHARGER - INSPECTION/CHECK
1. General
A. Decoupled static dischargers should be carefully checked on a periodic basis since failure to do so will impair radio reception and cause undue static interference.
2. Equipment and Materials
A. Megohmmeter (500 VDC Test Voltage, maximum 5 milliampere short circuit current) -Quadtech 1863 megohmmeter (or equivalent).
B. Bonding Meter (Ref 20-22-01)
3. Periodic Check of Decoupled Static Discharger
A. Prepare for check of Static Dischargers.
(1)
Remove pressure and power from the hydraulic systems for the applicable flight control surfaces (Ref 27-11-0 MP, 27-21-0 MP, 27-31-0 MP).
WARNING: MAKE SURE PRESSURE IS REMOVED FROM HYDRAULIC SYSTEMS. MAKE SURE HYDRAULIC POWER AND ELECTRICAL POWER ARE NOT SUPPLIED. IF HYDRAULIC PRESSURE IS PRESENT OR HYDRAULIC / ELECTRICAL POWER IS SUPPLIED, THE FLIGHT CONTROL SURFACES CAN MOVE. THIS CAN CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
(2)
Remove power from the electrical system (Ref 24-22-0 MP).
B. Visually check to determine that all dischargers are secure on mounting base and are not broken or missing.
C. Check dischargers for lightning damage as evidenced by a burning and roughening of the black conductive coating of the discharger and pitting of the metal discharger base.
D. Check for excessive erosion of discharger needles.
E. Check for excessive erosion of the discharger coating. Leading edge erosion of the dischargers should not extend back more than one-third the width of the discharger.
F. Check electrical bond between base and airplane structure per 20-22-01. Resistance for existing installations should not exceed:
0.05 ohms for dischargers mounted on metal panels.
0.5 ohms for dischargers mounted on fiberglass laminate or composite panels coated with aluminum flame spray and dischargers mounted on aluminum coated glass fabric.
5.0 ohms for dischargers mounted on composite panels without aluminum coating.
WARNING: MAKE SURE THAT THE BONDING METER IS RESISTANT TO EXPLOSION. IF NOT IT IS POSSIBLE THAT AN EXPLOSION OR FIRE CAN OCCUR.
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G. Use these precautions for possible fuel vapors when you use a megohmeter:
WARNING: USE THE PRECAUTIONS THAT FOLLOW WHEN YOU USE A MEGOHMMETER. IF YOU DO NOT USE PRECAUTIONS, THEN IT IS POSSIBLE THAT AN EXPLOSION OR FIRE CAN OCCUR.
(1)
Use the Quadtech 1863 megohmmeter or equivalent meter with a 500 VDC test voltage and a maximum 5 milliampeter short circuit current.
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