IPC-TM-650 EN 2022 试验方法.pdf - 第779页

D. Solder Tab — On the printed wiring traces as close to the termination as practicable. E. Press-Fit — On the pad of the plated-through hole as close to the termination as practicable. If the pad of the printed wiring b…

1.0 Scope

1.1

To evaluate the contact resistance of electrical contacts

at rated current.

2.0 Reference Documents

2.1

Information in this section is intended to parallel the test

method described in EIA-RS-364/TP-06.

3.0 Test Specimen

3.1

The mated contacts of a connector mounted and, when

required, terminated in its normal manner or a mated pair of

individual contacts.

NOTE:

When mated contact pairs, not requiring housings,

are tested, they shall be rigidly mounted in a fixture to provide

mechanical stability and to insure proper mating and orienta-

tion.

3.2 For contacts having a wire-hole, crimp or other termina-

tion, a 3-foot length of continuous wire may be used for heat

dissipation. The wire size shall be specified in the individual

contact or connector specification.

3.3 Voltage connections may be attached permanently by

soldering, crimping, or other suitable method.

3.4 Unless otherwise specified in the individual contact or

connector specification, the test sample shall not be cleaned

by any means prior to the test nor shall any lubricants or other

coatings be applied.

4.0 Apparatus

4.1 Voltmeter (10000 ohms per volt or greater)

The

meter accuracy shall be such that the voltage value is mea-

sured accurately within 5 percent.

4.2 Ammeter The meter accuracy shall be such that the

current value is measured accurately within 5 percent.

4.3 Power supply capable of delivering the required test cur-

rent.

5.0 Procedure

5.1

The contact resistance test shall be conducted using a

circuit as shown in Figure 1.

5.2 The current through the test sample shall be increased

to the value specified in the individual contact or connector

specification and shall be maintained until temperature stabili-

zation of the test sample at that current is attained. Tempera-

ture stability may be indicated by voltage drop stability.

5.3 The voltage drop across each pair of mated contacts

shall be measured with the voltmeter probes (or permanent

connection) positioned as follows:

A. Wire-Hole — On the contact with 1/8 inch of insulator.

B. Wrap-Post — On the wrap-post adjacent to the outer turn

of wire.

C. Crimp — On the wire (piercing the insulation) within 1/8

inch of insulator.

IPC-3-1-1

Figure 1 Test Set-up

2215 Sanders Road

Northbrook, IL 60062-6135

IPC-TM-650

TEST METHODS MANUAL

Number

3.1

Subject

Contact Resistance, 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

D. Solder Tab — On the printed wiring traces as close to the

termination as practicable.

E. Press-Fit — On the pad of the plated-through hole as

close to the termination as practicable.

If the pad of the printed wiring board constitutes one-half of

the mated contact pair, the voltmeter probe shall be posi-

tioned on the pad immediately adjacent to, but not touching,

the mating contact (not inside the insulator).

NOTE:

In case of an environment resistant (sealed) connec-

tor, the voltmeter probes shall be positioned as close to the

sealing grommets as practicable.

5.4 The contact resistance shall be calculated by dividing

the voltage drop reading by the current reading. The value

thus obtained for each contact shall not exceed the maximum

allowable contact resistance as defined in the individual con-

tact or connector specification.

5.5 For voltage drops less than 1.0 millivolt, the voltage drop

across each pair of mated contacts with the current succes-

sively in both directions through the test specimen shall be

measured. The contact resistance shall be calculated, in each

the forward and reverse directions, by dividing the voltage

drop reading by the current reading. The average of the two

resistance values thus obtained for each contact shall not

exceed the maximum allowable contact resistance as defined

in the individual contact for connector specification.

6.0 Notes

6.1

Acceptance criteria shall be established as the maxi-

mum level at which stable electrical contact is maintained.

This resistance is an inherent characteristic of any given con-

nector contact design and is (when the connector is properly

applied) well below that resistance level required for circuit

function.

IPC-TM-650

Number

3.1

Subject

Contact Resistance, Connectors

Date

7/75

Revision

Page2of2

1.0 Scope

1.1

To determine the ability of electrical contacts to with-

stand forces tending to displace them from their proper loca-

tion within the connector insert and to resist contact pull out.

These forces may be the result of (a) loads on wire connected

to the contact, (b) forces required to restrict contact ‘‘push

through’’ during assembly of removable type contacts into

connector inserts, during assembly of removable type con-

tacts into connector inserts, (c) forces produced by mating of

contacts during connector mating, (d) dynamic forces pro-

duced by vibration and shock during normal use of the con-

nectors, and (e) forces relating to bundling strains on wire.

2.0 Reference Documents

2.1

Information in this section is intended to parallel the test

method described in EIA-RS-364/TP-29.

3.0 Test Specimen

3.1

A plug and/or receptacle with a full complement of con-

tacts.

4.0 Apparatus

4.1

Force gauge, of suitable range and accuracy to provide

measured values accurate within 2 percent.

4.2 Contact removal and insertion tools as required by the

connector specification.

4.3 Steel test probes to adapt the force gauge plunger to

the front or wiring end of the particular contact (male, female,

or hermaphroditic) under test.

4.4 Device for applying the required load.

5.0 Procedure

NOTE:

All contact positions of the insert shall be filled during

this test.

5.1 All back shell hardware and compression rings shall be

removed to expose the wire side of the connector.

5.2 If possible, the test shall be conducted before wires

have been attached to the contacts.

5.3 The unmated plug or receptacle shall be mounted such

that an axial load can be applied by the force gauge. A mini-

mum of 1/4 inch clearance shall be provided on the opposite

side of the insert to permit any ‘‘push through’’ that might

occur.

NOTE:

The direction(s) in which the test is to be conducted

shall be determined from the individual connector specifica-

tion. If two-directional testing is required, the specified number

of samples shall be divided into equal groups (one group for

each test).

5.4 An axial load shall be applied to the contact at a rate of

approximately one (1) pound per second until the force speci-

fied in the detail specification is reached. The specified force

shall be maintained for a minimum of five (5) seconds.

6.0 Notes

6.1

Acceptance criteria shall be established in terms of (a)

the difference in contact position before and during the appli-

cation of the specified axial force and/or (b) the difference in

contact position before and after the application of the speci-

fied axial force.

2215 Sanders Road

Northbrook, IL 60062-6135

IPC-TM-650

TEST METHODS MANUAL

Number

3.2

Subject

Contact Retention, 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.

Page1of1

ASSOCIATION CONNECTING

ELECTRONICS INDUSTRIES