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| Figure 13-4 Overcurrent relay: (A) Plunger type. |

| relay may be set to raise the plunger at any predetermined value within the range of the solenoid. The lower the position of the plunger, the more current that is required to pull it into the closing position. Current settings may also be varied by taps in the coil. |

| Inverse time delay in the operation of this relay is obtained by means of a bellows (leather or rubber) arranged to retard the motion of the movable contacts. Time is varied by changing the setting of the needle valve that governs the escape of air from the bellows. An oil-filled dashpot is sometimes |

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