 |
|||
|
|
|||
| ||||||||||
|
|  MIL-R-5757H
3.4.7.5 Solder dip (retinning) leads. The manufacturer may solder dip/retin the leads of product
supplied to this specification provided the solder dip process has been approved by the qualifying
activity.
3.4.7.5.1 Qualifying activity approval. Approval of the solder dip process will be based on one of the
following options (NOTE: Solder dip of gold-plated plug-in leads is not allowed.) All visual examination
criteria shall be in accordance with method 208 of MIL-STD-202:
a. The manufacturer shall use a qualifying activity approved solder dip process for retinning.
b. When the lead originally qualified was not hot solder dip lead finish 52 as prescribed above,
approval for the process to be used for solder dip shall be based on the following test procedure:
(1) Six samples for each style and lead finish are subjected to the manufacturer's solder dip
process. Following the solder dip process, the relays shall be subjected to group A2 and
group A4 inspections.
(2) Three of the six samples are then subjected to the solderability test (see 3.6). No visual
defects are allowed.
(3) Remaining three samples are subjected to the resistance to soldering heat test (see 3.19).
(4) All six samples shall be subjected to group A2 and group A4 inspections. Minor scratching of
the terminals due to insertion into test sockets shall not be cause for rejection.
3.4.7.5.2 Solder dip/retinning options. The manufacturer may solder dip/retin as follows:
a. After the 100 percent group A1 screening tests and before the group A3 solderability test:
Following the solder dip/retinning process, insulation resistance (all terminals to case), seal, and
visual/mechanical inspection shall be performed.
b. As a corrective action: If the lot fails the group A solderability test, insulation resistance (all
terminals to case), seal, and visual/mechanical inspection shall be performed.
c.
For relays that have been subjected to and passed group A inspection: Following the solder
dip/retinning process, insulation resistance (all terminals to case), seal, and visual/mechanical
inspection shall be performed.
3.5 Screening (internal moisture; see 4.6.2; run-in, see 4.6.3). The contact miss detector's monitoring
level shall be less than 100 ohms for relays tested during cycling. Unless otherwise specified (see 3.1),
any relay shall have a final insulation resistance measurement of 10,000 megohms or greater.
3.6 Solderability (see 4.6.4). The critical (examination) area of solid wire lead and pin terminals shall
be at least 95 percent covered with a continuous new solder coating in accordance with method 208 of
MIL-STD-202. For solder-lug terminals greater than .045 inch (1.14 mm) in diameter, 95 percent of the
total length of fillet, which is between the standard wrap wire and the terminal, shall be tangent to the
surface of the terminal being tested, and shall be free of pinholes, voids, etc. A ragged or interrupted
line at the point of tangency between the fillet and the terminal under test shall be considered a failure.
3.7 Seal (see 4.6.5).
3.7.1 Reed relays. There shall be no evidence of leakage.
8
|
|
Privacy Statement - Press Release - Copyright Information. - Contact Us |
Click
here for thousands of PDF manuals