MIL-DTL-28788 Switches, Air And Liquid Flow, Sensing, General Specification ForThis specification covers the general requirements for flow switches intended primarily for use in equipment to sense velocity and flow of air or liquid.

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MIL-DTL-28788C

C is a straight pipe equal to length to a + d + b.

ĆP1 minus ĆP2 is the amount of ĆP chargeable to the test unit.

FIGURE 1. Differential test set-up.

4.7.7 High temperature (see 3.11). Switches shall be subjected to the highest nonoperating

temperature specified (see 3.1 and 6.1), for a minimum of 12 hours. After this period, the temperature

shall be reduced to the highest operating temperature specified and held for 2 hours. Then, while at this

temperature, the switches shall be tested in accordance with 3.8, and the operating points shall be within

tolerances specified.

4.7.8 Low temperature (see 3.12). Switches shall be subjected to the lowest nonoperating

temperatures specified (see 3.1), for a minimum of 12 hours. After this period, the temperature shall be

changed to the lowest operating temperature specified and held for 2 hours. Then, while at this

temperature, the switches shall be tested in accordance with 4.7.4, and the operating points shall be

within tolerances specified.