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Page 283

| Figure 14-15 Relay contact shapes. |

| pitted, they must be cleaned with a burnishing tool, making sure that the original shape is retained. |

| Solid silver or silver-plated contacts may be cleaned with a cloth or brush dipped in cleaning fluid, then polished with a dry cloth. The dark discoloration found on silver and silver-plated relay contacts is silver oxide, which is a good conductor and should be left alone unless the contacts need to be cleaned or dressed for other reasons; it may be removed with a cloth moistened in cleaning fluid. Deeply pitted contacts may be reshaped very carefully with a fine file or fine sandpaper. Very badly burned or pitted contacts should be replaced. |

| Contact arms should be adjusted to the correct positions if they have been moved during cleaning, taking care that the settings of the relays are not changed. |

| Other items. If an ac relay is excessively noisy, it may be due to some loose connection or from a mechanical misalignment of the armature or |

| Figure 14-16 Cleaning relay contacts. |

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