MIL-PRF-22710 Switches, Code Indicating Wheel \(Printed Circuit\), Thumbwheel And Push-Button, General Specification ForThis specification covers the general requirements for illuminated and non-illuminated, thumbwheel \(see 6.4.1\), and push-button, printed circuit rotary switches having unsealed and sealed modules and the associated hardware. These switches are designed for low power alternating current \(ac\) and direct current \(dc\) switching applications for use in electronic and communication equipment. Procurement of switches and mounting hardware will require additional data, giving detailed electrical and mechanical requirements, tolerances, and applicable additions and exceptions to the general requirements and tests specified herein \(see 6.2\).

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MIL-PRF-22710H

3.8 Rotational torque or operating force (as applicable, see 3.1 and 4.5.5).

3.8.1 Rotational torque (applicable to external drive shaft switches. When switches are tested as specified in

4.5.5.1, the torque required to rotate the shaft from each detent position to the next shall be within the specified limits

(see 3.1).

3.8.2 Operating force (applicable to switch modules or stacked switch modules). When switches are tested as

specified in 4.5.5.2, the tangential force required to rotate the shaft from each detent position to the next shall be

within the specified limits (see 3.1).

3.9 Stops (when applicable). When switches with stops are tested as specified in 4.5.6, there shall be no broken,

loose, deformed, or displaced parts, nor shall there be any slippage of moving parts.

3.10 Thermal shock. When switches are tested as specified in 4.5.7, there shall be no mechanical or electrical

damage, loosening of rivets or other fastening devices.

3.11 Terminal strength (applicable to switches having solder-type terminals, see 3.1 and 4.5.8).

3.11.1 Pull. When switches are tested as specified in 4.5.8.1.1 and 4.5.8.1.2, the terminals shall withstand the

specified load without breaking or affecting the switching arrangement.

3.11.2 Bend (when applicable). When switches with terminals bent permanently out of shape are tested as

specified in 4.5.8.2, there shall be no breakage of terminals or visible cracks in either the terminals or the insulating

material.

3.12 Strength of mounting bushing (when applicable, see 3.1). When switches are tested as specified in 4.5.9,

there shall be no damage to the switch, or loosening or twisting of the bushing relative to the switch front plate

assembly.

3.13 Vibration. When switches are tested as specified in 4.5.10, any pair of mating contacts shall not open for a

period of time longer than 1 microsecond (ms) including bounce before reclosing, unless otherwise specified (see

3.1). There shall be no change in shaft position, or evidence of broken, loose, deformed, or displaced parts.

3.14 Shock (see 4.5.11). When switches are tested as specified in 4.5.11.1, mating contacts shall not open for a

period of time longer than 1 millisecond including bounce, unless otherwise specified (see 3.1). When tested as

specified in 4.5.11.2, contacts shall not open for a period longer than 5 milliseconds including bounce, unless

otherwise specified (see 3.1), before returning to the closed position before the end of the first bounce. There shall

be no change in shaft position, or evidence of broken, loose, deformed, or displaced parts.

3.15 Insulation resistance. When measured as specified in 4.5.12, the insulation resistance shall be greater than

1,000 megohms, unless otherwise specified (see 3.1).

3.16 Lamp retention (when applicable, see 3.1). When switches are tested as specified in 4.5.13, the captive

means shall be capable of retaining the lamp retention adapter.

3.17 Seal (when applicable, see 3.1). When switches are tested as specified in 4.5.14, the following requirements

shall apply.

3.17.1 Method I (mounting) (see 4.5.14.1). During the seal test, there shall be no evidence of a continuous stream

of air bubbles. During the dielectric withstanding voltage test, the leakage current shall not exceed 1.0 milliampere.

3.17.2 Method II (mounting) (see 4.5.14.2). There shall be no evidence of leakage as evidenced by a continuous

stream of air bubbles.

3.18 Dielectric withstanding voltage. When switches are tested as specified in 4.5.15, there shall be no arcing,

flashover, breakdown of insulation or damage, and the leakage current shall be not greater than 0.5 milliampere.

3.19 Moisture resistance (see 4.5.16). When switches are tested as specified in 4.5.16.1 or 4.5.16.2, the

insulation resistance shall be greater than 25 megohms, unless otherwise specified (see 3.1). At the conclusion of

the test, there shall be no evidence of measling, corrosion, breaking, cracking, spalling, or loosening of terminals

outside the confines of the terminal anchoring device, and mounting hardware shall be readily removable. There

shall be no peeling or chipping of the finish.