Subtask 20-28-00-869-083-A

 B. Static dischargers
 (Ref. TASK 20-28-00-720-005), (Ref. TASK 20-28-00-720-008).

 -------------------------------------------------------------------------------| CATEGORY | LOCATION | PROCEDURE | RESISTANCE | | | | | (MAX. VALUE) | |----------------|--------------------------|---------------|-----------------| | Static | - between the grounding | Ref. TASK | 50 milliohms | | dischargers | point on the main | 202800720005 | | | installed on | landing gear and all | | | | the wing | the static dischargers | | | | | (metallic part) except | | | | | zones 470 and 480 (aft | | | | | movable fairing of the | | | | | pylon) | | | | | | | | | | - between the grounding | Ref. TASK | 50 Kohms | | | point on the main | 202800720008 | | | | landing gear and the | | | | | static dischargers | | | | | (metallic part) fitted | | | | | on the aft movable | | | | | fairing of the pylon | | | | | (zones 470 and 480) | | | | | | | | | Static | - between the THS bonding| Ref. TASK | 50 milliohms | | dischargers | leads and all the | 202800720005 | | | installed on | static dischargers | | | | the THS, fin | (metallic part) | | | | and rudder and | | | | | elevators | | | | -------------------------------------------------------------------------------
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 TASK 20-28-00-720-001

 Low-Current Test Method
 1.
 Reason for the Job

__________________
 Self Explanatory

 2.
 Job Set-up Information

______________________
 A. Referenced Information
 -------------------------------------------------------------------------------REFERENCE DESIGNATION -------------------------------------------------------------------------------
20-28-00-869-002 Table of the Maximum Permitted Resistance Values
 3. Job Set-up
__________ Subtask 20-28-00-869-053
 A. Equipment
 (1) Variable Power Supply Unit (PSU), continuous output test current of 10 amperes (24 volts nominal).
 NOTE : The ratings of the wires that connect the PSU to the
____ components on which you do the test must be :
 -at least 25% higher than the maximum current used in the test
 -for the low-current test, the wire rating = 13 amperes.
 (2)
 Ammeter - FSD 10 amperes.

 (3)
 Millivoltmeter - multirange

 -------------------------------------------------------------------------------| RANGE | 1 | 2 | 3 | 4 | 5 | |---------|-------------|--------------|-------------|-------------|----------| | FSD | 2mV | 20mV | 200mV | 2V | 20V | -------------------------------------------------------------------------------
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 4. Procedure
_________

 Subtask 20-28-00-420-078
 A. Measurement of the Electrical Resistance CAUTION : MAKE SURE THAT YOU DO NOT CAUSE DAMAGE TO THE EQUIPMENT OR THE
_______
 STRUCTURE WHEN YOU USE SHARP-POINT PRODS.

 CAUTION : MAKE SURE THAT THE TEST EQUIPMENT IS CORRECTLY INSTALLED BEFORE
_______
 YOU MEASURE THE BONDING VALUES.

 (1) Connect the PSU. NOTE : Make all the connections as near as possible to the bonding or
____
 grounding point.

 NOTE : Make sure that the connections are clean and have no grease.
____
 (2)
 Adjust the PSU to get a test current of 10 amperes on the ammeter. NOTE : Start with the PSU at its low setting.

____

 (3)
 Put one prod of the millivoltmeter on the structure adjacent to the bonding point and the other prod on the component (put them adjacent to the bonding points and make sure that there is a good contact).

 NOTE : Start the test with the millivoltmeter in the 20V range. Go
____ down in sequence through the ranges to get the highest movement of the needle on the scale.
 (4)
 Measure and write the values.

 (5)
 Remove the prods, de-energize the power supply and disconnect the test circuit.

 (6)
 Calculate the resistance in milliohms:

 -divide the voltage in millivolts by the current in amperes.

 (7)
 Make sure that the measured values are not higher than the maximum permitted values. (Ref. TASK 20-28-00-869-002)

 5. Close-up
________ Subtask 20-28-00-942-090
 A. Close Access
 (1) Make sure that the work area is clean and clear of tool(s) and other items.
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 TASK 20-28-00-720-005

R R  Check of the Electrical Bonding of the Different Components (But not the Fluid Systems and the Components Installed on Composite materials)
　
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