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

4.5.15 Dielectric withstanding voltage (see 3.18). Switches shall be tested in accordance with 4.5.15.1, and when

applicable (see 3.1 and 6.2.2), in accordance with 4.5.15.2.

4.5.15.1 At atmospheric pressure. Switches shall be tested in accordance with method 301 of MIL-STD-202.

Unless otherwise specified (see 3.1), the following details shall apply:

a. Magnitude of test voltage: 1,000 volts.

b. Nature of potential: AC.

c. Points of application of test voltage: Each test applies for each switch section:

(1) Between all mutually insulated terminals in a sufficient number of dial positions to check all possible

leakage paths between terminals.

(2) Between all terminals tied together and frame or ground.

d. Measurements during test: Leakage current.

After the test, switches shall be examined for evidence of arcing, flashover, breakdown of insulation and damage.

4.5.15.2 At reduced barometric pressure. Switches designed for operation above 10,000 feet shall be tested as

specified in 4.5.15.1 and in accordance with method 105 of MIL-STD-202. The following details shall apply:

a. Method of mounting: By normal mounting means on a corrosion-resistant panel.

b. Test-condition letter: C or D, as specified (see 3.1).

c. Test during subjection to reduced pressure: The switch contacts specified in 4.5.15.1c shall be tested at 450

volts rms, unless other specified (see 3.1).

After the test, switches shall be examined for evidence of arcing, flashover, breakdown of insulation, and damage.

4.5.16 Moisture resistance (see 3.19). Switches shall be tested in accordance with 4.5.16.1 or 4.5.16.2, as

specified (see 3.1 and 6.2.2).

4.5.16.1 Method I. Switches shall be tested in accordance with method 106 of MIL-STD-202. The following details

and exceptions shall apply:

a. Mounting: Switches shall be mounted on a corrosion-resistant metal panel. Half of the switches shall be

tested in the "up" position and half shall be tested in the "down" position.

b. Initial measurement: Not applicable.

c. Polarization: During step 1 to step 6 inclusive, a polarization voltage of 100 volts dc shall be applied between

two terminals tied together on opposite sides and adjacent to a throughbolt, or a terminal adjacent to a

grounded metal portion if no through bolting is used, and the metal panel. Polarization voltage shall also be

applied to two other adjacent terminals elsewhere on the switch section. One section of each switch should

be so tested. The negative polarity shall be applied to the metal panel.

d. Step 7a and step 7b shall not apply.

e. Loading voltage: Not applicable.