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5.0
Conditioning
5.1
Prior to testing, expose one-third of the specimens for 12 days in an oven
uniformly maintained at 160º ±5º F; one-third of the specimens in a horizontal
position for 24 hours under a continuous water shower; and one-third of the
specimens in an atmosphere uniformly maintained at 73º ±5º F and 50 ±5
percent relative humidity.
5.2
Unless otherwise specified, all specimens shall be placed in the desiccating
chamber for a minimum of 24 hours immediately before testing, as specified in
section 6.
5.3
Test environment. Perform tests in an atmosphere uniformly maintained at 73º
±3.5º F and a dry condition of less than 15 percent relative humidity. This relative
humidity can be obtained by inserting a dish (approximately 4 inches in diameter)
containing 50 grams of anhydrous calcium chloride into the test chamber. The
anhydrous calcium chloride shall be replaced daily.
6.0
Procedure
6.1
Calibration
6.1.1
6.1.2
6.1.3
6.1.4
6.1.5
6.1.6
6.1.7
6.1.8
6.2
Each specimen shall be mounted vertically between the electrodes and the wing
nuts tightened to insure intimate contact between specimen and electrodes.
Turn on all components and allow to warm up, as noted in the operations
manual for the particular item.
Set "multiplier" switch of the electrometer at 10 and the "operate" switch
at "zero check".
Close the ground switch and adjust the high voltage for 5kV output.
Mount a 1/8-by 3-by 5-inch aluminum panel between the electrodes in
the test chamber so that the detector head is directly in the center of the
panel. Tighten the four wing nuts to secure the panel.
Adjust the speed of the recorder chart at 1 inch minimum, move operate
switch to "operate" position and close the high voltage switch to apply
5kV to test panel.
Move multiplier switch until the meter needle reads maximum without
exceeding the limits of the meter. Check to see if the charge indicated by
the meter is identical to that being recorded on the chart.
Close ground switch to remove the charge. When the meter reaches
zero, stop chart and move operate switch on electrometer to "zero
check" position.
Repeat this procedure for both positive and negative charges.
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