IPC-TM-650 EN 2022 试验方法.pdf - 第570页

1 Scope The dielectric strength test (also called high- potential [Hi-Pot], over potential, or voltage breakdown) con- sists of the application of a test voltage for a specific time between mutually insulated portions of…

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6.1
The
dielectric breakdown of the material may be
adversely affected if the drilling process used to produce the
holes is inadequate. Use of a sharp high speed drill is recom-
mended to prevent burning the material or producing rough
holes.
6.2 This test requires voltages which are life threatening. The
High Voltage Tester must be installed and operated in accor-
dance with the manufacturer’s instructions. If the test cham-
ber is not totally enclosed, with a safety interlock, extreme
care must be exercised in performance of the test.
IPC-TM-650
Number
2.5.6
Subject
Dielectric
Breakdown of Rigid Printed Wiring Material
Date
5/86
Revision
B
P
age3of3
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1 Scope The dielectric strength test (also called high-
potential [Hi-Pot], over potential, or voltage breakdown) con-
sists of the application of a test voltage for a specific time
between mutually insulated portions of a printed board or
between insulated portions and ground. This is used to prove
that the printed board can operate safely at its rated voltage
and withstand momentary overpotentials due to switching,
surges, and other similar phenomena.
2 Applicable Documents
ASTM D 149
Standard Test Method for Dielectric Break-
down Voltage and Dielectric Strength of Solid Electrical Insu-
lation Materials at Commercial Power Frequencies
3 Test Specimen Three 102 mm x 102 mm [4.016 in x
4.016 in] squares of glass epoxy laminate materials having
1 ounce (0.0343 mm [0.00135 in] nominal) copper foil lami-
nates on one side, and having the test specimen polymer film
applied to the copper surface (see specimen preparation).
4 Apparatus
4.1
Any high voltage potential test equipment capable of
providing voltage increases of 500 VDC per second, up to at
least 10,000 VDC (see Section 6).
4.2 A standard Type 1 electrode per ASTM D 149, with a 51
mm [2.0 in] diameter, 25 mm [1.0 in] thick, with edges
rounded to 6.4 mm [0.25 in.] radius to cover the test surface.
5 Procedure
5.1 Preparation of Test Specimen
5.1.1
Cut the laminate specimen to 102 mm x 102 mm
[4.016 in x 4.016 in] and sand the edges lightly.
5.1.2 If double clad material is used, etch off all copper foil
on one side.
5.1.3 Clean the copper foil surface thoroughly, per the poly-
mer manufacturer’s recommendations, prior to applying poly-
mer coating.
5.1.4 Apply a film of the polymer test material on an area of
76.2 mm x 76.2 mm [3.0 in x 3.0 in] at the center of the cop-
per clad surface. A pinhole free film is essential.
5.1.5 Cure the polymer coating per manufacturer’s recom-
mendations.
5.2 Test
5.2.1
Clip the ground terminal of the tester over the thick-
ness of the copper foil and substrate, being careful not to let
the clip extend inward to the polymer coating (see Figure 1).
5.2.2 Place the positive electrode on top of test panel at the
center. Make certain the electrode and clip are electrically iso-
lated by the test polymer film.
5.2.3 Set up the potential voltage tester. Increase the volt-
age 500 VDC per second, until specimen exceeds require-
ment or breakdown occurs.
5.2.4 Measure the coating thickness of each of the test
specimens to the nearest 0.0025 mm [0.0001 in] in at least
four locations. Compute the average coating thickness and
standard deviation.
5.3 Evaluation Determine the dielectric strength, E
D
, using:
E
D
=
V
BD
t
where t is the thickness of the specimen, to the nearest
0.0025 mm [0.0001 in], measured in 5.2.4 and V
BD
is
the breakdown voltage measured in 5.2.3. Record results as
‘‘V/mm’’ or ‘‘V/in.’’
6 Notes
6.1
Suggested source for tester: Hipotronics Model HD-140
from Hipotronics, Inc. Brewster, NY 10509, or equivalent.
6.2 Safety must be exercised because of the potential dan-
ger of electrical shock.
IPC-2561-1
Figure 1
3000 Lakeside Drive, Suite 309S
Bannockburn, IL 60015-1249
IPC-TM-650
TEST METHODS MANUAL
Number
2.5.6.1
Subject
Solder Mask - Dielectric Strength
Date
03/07
Revision
B
Originating Task Group
Solder Mask Performance Task Group (5-33b)
Material in this Test Methods Manual was voluntarily established by Technical Committees of IPC. This material is advisory only
and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by IPC.
Page1of1
ASSOCIATION CONNECTING
ELECTRONICS INDUSTRIES
®
1.0
Scope
This
method describes a technique for evaluat-
ing the ability of an insulating material to resist electrical break-
down perpendicular to the plane of the material when sub-
jected to short term, high voltages at standard AC power
frequencies of 50-60 Hz.
1.1
Applicability and Use of Data
This
method may be
used on material of any thickness up to approximately 0.125
inch, however, for material over 0.020 inch, other methods
such as dielectric breakdown are normally used to character-
ize a material’s electrical integrity. Results of this test may be
drastically affected by moisture content, and results obtained
using different preconditioning may not be comparable.
This method uses an oil medium to prevent flashover on a
small specimen and results may not be comparable to tests
run in air. Values obtained using this method should not be
used for predicting the insulating ability of ultra thin metal clad
laminates.
The values determined by this method generally decrease with
increasing specimen thickness for otherwise identical material.
This method is based on the techniques described in ASTM
D149.
2.0
Applicable Document
ASTM D149
Standard
Test Method for Dielectric Breakdown
Voltage and Dielectric Strength of Solid Electrical Insulating
Materials at Commercial Power Frequencies
3.0
Test Specimens
3.1 Number
Three
specimens shall be prepared unless
otherwise specified.
3.2
Form
Specimens
should be 4.0 inch ± 1.0 inch X 4.0 ±
1.0 inch; however, size is not critical as long as no flashover
occurs around the edges.
3.3
Location
Specimens
shall be cut by any convenient
means from both edges
1
and
the center of the laminate
(except no specimen shall be taken closer than 1 inch from
the edge of full size sheets).
3.4
Foil Clad Material
Foil
clad materials shall have all
metal cladding removed by etching and should be thoroughly
cleaned prior to conditioning or testing.
3.5
Uncured Material
Uncured
material must be fully
cured. Under normal conditions, two ply lamination is recom-
rnended for comparison of prepreg material. Single ply lami-
nates are recommended for cover lays and similar products
designed for single ply usage.
4.0
Apparatus/Materials
4.1
High
voltage breakdown tester, 25 KV, minimum with an
adequate current rating
2
,
a motorized control capable of 500
volts per second rate of rise and a meter capable of indicating
breakdown voltage within 5% over the entire range of actual
breakdown voltages (generally 1 KV to 20 KV).
4.2
Oil
tank filled with insulating oil
3
.
4.3
Electrode
test set 2 inch diameter electrodes with 1/4
inch radius on the edge of the electrodes and 50 g. ± 2g.
load applied by the weight of upper electrode (in air).
4.4
Two
high voltage test leads (leads rated in excess of the
tester voltage capability are recommended).
4.5
Micrometer
capable of resolving at least 0.0001 inch.
Note: For accurate measurement of material under 0.005 inch
test accuracy may be severely limited by the ability to measure
the specimen accurately.
4.6
Constant
temperature water bath, capable of maintain-
ing 50°C ± 2°C, filled with distilled water.
1.
Edges: For a reinforced laminate the specimens shall be from opposite edges of the reinforcement.
2. Current capacity: 40 milliamps is normally satisfactory.
3. Insulating oil: Shell Dial AX Insulating Oil has been found suitable for breakdowns up to 100 KV.
The
Institute for Interconnecting and Packaging Electronic Circuits
2215 Sanders Road Northbrook, IL 60062
IPC-TM-650
TEST
METHODS MANUAL
Number
2.5.6.2
Subject
Electric
Strength of Printed Wiring Material
Date
8/97
Revision
A
Originating Task Group
N/A
Material
in this Test Methods Manual was voluntarily established by Technical Committees of the IPC. This material is advisory only
and its use or adaptation is entirely voluntary. IPC disclaims all liability of any kind as to the use, application, or adaptation of this
material. Users are also wholly responsible for protecting themselves against all claims or liabilities for patent infringement.
Equipment referenced is for the convenience of the user and does not imply endorsement by the IPC.
P
age1of3
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