MIL-PRF-55629 Circuit Breakers, Magnetic, Unsealed Or Panel Seal, Trip-Free, General Specification ForThis specification covers the requirements and test procedures for single and multipole, trip-free, unsealed, magnetic circuit breakers with current ratings of 0.2 amperes to 100 amperes inclusive, up to and including 240 volts, 400 Hertz, 480 volts, 60 Hertz alternating current \(ac\) and 125 volts direct current \(dc\), \(see 6.1\). These circuit breakers may also include auxiliary contacts \(see 6.6.1\) for monitoring circuits. A voltage sensitive pole is also available in a four pole device. Panel seal mounts are available in 0.2 amperes through 50 amperes. Designers are WARNED that these circuit breakers may contain a pure tin finish on some of the component parts \(see 6.5\).

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MIL-PRF-55629E

3-POLE CIRCUIT BREAKER TEST

NOTE: See figure 3 for legend and notes.

FIGURE 8. DC interrupting capacity test operations (duty cycle) and circuit wiring.

4.8.20 Panel seal (see 3.24) (when specified, see 3.1). Circuit breakers shall be secured by their normal mounting

means to a suitable test jig. A suggested test jig is shown on figure 9. The test jig shall be immersed in a water-filled

glass container containing a wetting agent, with the circuit breaker completely submerged. An air pressure of 15

pounds per square inch gage shall be applied to the test jig for approximately one-half hour. The circuit breaker and

connection to the test jig shall be observed for any visible air bubbles indicative of leakage, either in the form of a

continuous stream, or as bubbles emanating at regular intervals. The test shall then be repeated by applying air

pressure in the opposite direction by reversing the cover.