IPC-TM-650 EN 2022 试验方法.pdf - 第806页

B. The rate of change of frequency (Hz/min.) shall be con- stant for any one band. C. The ratio of the rate of change of frequency of each band to the maximum frequency of that band shall be approxi- mately the same as t…

5.3.3 Resonant modes of the test sample shall be deter-

mined by varying the frequency of the applied sinusoidal vibra-

tion slowly through the frequency range from 55 to 2000 Hz

at an amplitude of less than±2Gpeak. The test sample shall

be vibrated at a peak acceleration of ± 10G for 5 minutes at

each critical resonant frequency observed (see Table 1, Note

3).

5.3.4 The test sample shall be subjected to random vibration

in accordance with Test Condition F, Table 1 and Figure 4.

5.3.5 During the test along each axis, the contacts shall be

continuously monitored for discontinuities in excess of 1

microsecond.

6.0 Notes

6.1

Acceptance criteria shall be established in terms of one,

or any combination, of the following:

A. Loss of continuity during or after any imposed shock.

B. Mechanical damage.

C. Increase in contact resistance.

D. Decrease in contact normal force.

6.2 A linear rate of change of frequency is permissible in

place of the specified logarithmic rate under the following con-

ditions:

A. The frequency range above 55 Hz shall be subdivided into

not less than three bands. The ratio of the maximum fre-

quency to the minimum frequency in each band shall not

be less than two.

IPC-3-12-4

Figure 4 Random Vibration Input

IPC-TM-650

Number

3.12

Subject

Vibration, Connectors

Date

7/75

Revision

Page5of6

B. The rate of change of frequency (Hz/min.) shall be con-

stant for any one band.

C. The ratio of the rate of change of frequency of each band

to the maximum frequency of that band shall be approxi-

mately the same as that ratio for every other band.

EXAMPLE:

As an example of the computation of rates of

change, assume that the frequency spectrum has been

divided into three bands, 55 to 125 Hz, 125 to 500 Hz,

and 500 to 2000 Hz, in accordance with 6.2A. Let the

(constant) ratio of rate of frequency change in Hz/min. to

maximum frequency in Hz be k for each band. Then the

rates of change for the three bands will be 125k, 500k

and 2000k, respectively. The times, in minutes, to traverse

the three frequency bands will therefore be, respectively,

125−55

125k

500−125

500k

and 2000−500

2000k

EXAMPLE:

If the range traverse time is 30 minutes –

30 =

125k

375

500k

1500

2000k

from which: k = 0.0687

The required maximum constant rates of frequency

change for the three bands are therefore 8.55, 34.2 and

137 Hz/min., respectively, and the times of traverse of the

bands are 8.2, 10.9 and 10.9 minutes, respectively.

IPC-TM-650

Number

3.12

Subject

Vibration, Connectors

Date

7/75

Revision

Page6of6

1.0 Scope

1.1

To determine the ability of the connector to operate

safely at its rated voltage and to withstand momentary over-

potentials due to switching, surges, or other similar phenom-

ena. The dielectric withstanding voltage test is also called

high-potential, over-potential, or dielectric-strength test, but

differs from a dielectric-breakdown test as described in para-

graph 6.2.

2.0 Reference Documents

2.1

Information in this section is intended to parallel the test

method described in EIA-RS-364/TP-20.

3.0 Specimen

3.1

A plug, receptacle or mated combination as specified in

the individual connector specification.

4.0 Apparatus

4.1

High voltage source adjustable to within ± 5% of

required test voltage (DC or RMS) and capable of delivering a

minimum current of 1 milliampere.

4.2 Leakage current meter accurate to ± 5% of reading.

NOTE:

Commercial devices are available that incorporate

the voltage source and leakage monitor, as well as a fault

monitor (e.g., light, bell, automatic shut-down) into one instru-

ment.

4.3 Altitude chamber capable of maintaining a simulated alti-

tude at temperature extremes of –65°C to + 125°C.

5.0 Procedure

WARNING:

POTENTIALS USED DURING THIS TEST MAY

PROVE HAZARDOUS TO PERSONNEL. TAKE PRECAU-

TIONS TO PROTECT PERSONNEL FROM ACCIDENTAL

EXPOSURE TO THESE TEST POTENTIALS.

5.1 The withstanding voltage shall be applied between indi-

vidual pairs of immediately adjacent contacts and between the

shell and/or engaging hardware (if they exist) and the closest

individual contact(s). The method of connection of the test

voltage if significant shall be specified in the individual connec-

tor specification. When special preparations or conditions

such as special test fixtures, reconnection, or grounding iso-

lation are required, they shall be so specified.

5.2 Under the specified conditions of temperature and baro-

metric pressure, the test voltage shall be increased from zero

to the specified value as uniformly as possible at an approxi-

mate rate of 500 volts (DC or RMS) per second unless other-

wise specified.

5.3 The test voltage shall be applied for a minimum period

of 60 seconds during which time the connector under test

shall be observed for evidence of disruptive discharge or for

leakage current in excess of one (1) milliampere.

5.4 The test voltage shall be gradually reduced to zero to

avoid surges.

6.0 Notes

6.1

Acceptance criteria shall be established by the lack of

disruptive discharge as evidenced by flashover (surface dis-

charge), sparkover (air discharge), or breakdown (puncture

discharge), or of excessive leakage current. Resistance to

these conditions is an inherent characteristic of connector

geometry (e.g., contact spacing), contact configuration (e.g.,

smooth contours), and insulator materials.

6.2 Dielectric withstanding voltage shall be defined as 75

percent of the nominal dielectric breakdown voltage mea-

sured under the same conditions of altitude and temperature.

6.3 Simulated altitudes used during this test shall be

selected from those shown in Table 1.

2215 Sanders Road

Northbrook, IL 60062-6135

IPC-TM-650

TEST METHODS MANUAL

Number

3.13

Subject

Withstanding Voltage, Connectors

Date

7/75

Revision

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.

Page1of2

ASSOCIATION CONNECTING

ELECTRONICS INDUSTRIES