MIL-DTL-26126 Relays, Electrical, Overvoltage, Dc, General Specification ForThis specification covers the general requirements for dc overvoltage sensing relays for use in electrical applications. Relays covered by this specification are capable of meeting the electrical and environmental requirements when mounted directly to the structure of aircraft, missile, spacecraft, ship, and other primary vehicles or in ground support and shipboard equipment.

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MIL-DTL-26126C

4.6.15 Salt spray (see 3.5.14). Relays shall be tested in accordance with method 101 of MIL-STD-

202. The following details and exceptions apply:

a. Test condition letter: B.

b. Applicable salt solution: 5 percent.

c. Examination after test: Relays shall be examined for evidence of peeling, chipping,

blistering of the finish, and exposure of base metal due to corrosion. Type I relays shall

be tested for calibration as specified in 4.6.3.

4.6.16 Thermal shock (see 3.5.15). Relays shall be tested in accordance with method 107 of MIL-

STD-202. The following details and exceptions apply:

a. Relays shall be suspended in the test chamber by twine or other nonheat-conducting

material.

b. Test condition letter: A. The minimum exposure time for steps 1 and 3 shall be 1 hour

each.

c. Measurements after cycling: Relays shall be visually examined for cracking, peeling,

and flaking of the finish. Calibration shall then be conducted as specified in 4.6.3.

4.6.17 Seal (see 3.5.16). Relays shall be tested in accordance with method 112 of MIL-STD-202. The

following details apply:

a. Test condition letter: C (procedure III or IV at the option of the manufacturer).

b. Leakage-rate sensitivity:

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(1) Type I relays: 1 x 10 atm cc/s. When a separate hermetically sealed

switching device is a part of the relay, each device shall be individually tested

for hermetic seal.

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(2) Type II relays: Greater than 2 cubic inches in volume - 1 x 10 atm cc/s; 2

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cubic inches or less - 1 x 10 atm cc/s.

c. Reduced pressure of chamber and duration of pressurization (procedure IV): Below 5

millimeters of mercury until the leak detector reading is stabilized.

d. Measurements after test: Not applicable.

4.6.17.1 Nonhermetically-sealed and hermetically-sealed (potted) relays (alternate method) (see

3.5.16.3). Relays shall be tested as follows:

a. Prior to installing a gasket on the relay header (if a gasket is used), the relay shall be totally

immersed in a container of "tap" water. (The term "tap" water as used here means ordinary

drinking water that has not been altered in any way, such as by the addition of any other

substance, distilling, etc.) The part of the relay closest to the surface of the water shall be a

minimum of 1.00 inch (25.4 mm) below this surface.

b. The container and water-covered relay shall then be placed in a vacuum chamber. The chamber