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Page 44

| Figure 3-1 Modern cluster mounting of distribution transformers on a pole. |

| have two lugs welded directly on the case; these lugs engage two bolts on the pole from which the whole apparatus hangs securely. This method, which is known as direct mounting eliminates the need for cross arms and hanger irons (as was done in the past), thus saving a considerable amount of material and labor. |

| In the past, smaller transformers were hung from crossarms by means of hanger irons, which were two flat pieces of steel with their top ends bent into hooks with squared sides (Fig. 3-3A). The transformer was bolted to these pieces of steel, the assembly was raised slightly above the crossarm and then lowered so that the hooks on the hanger irons would engage the crossarm. Many such installations still exist. Installing larger transformers is illustrated in Fig. 3-3B. |

| Transformers may be raised to their position by means of block and tackle as shown in Fig. 3-4 (on page 46), with one set of blocks attached to a stub extension attached to the top of the pole and the other to a sling attached to the transformer; a guide line attached to the transformer keeps it under control during the lifting process. Smaller units are lifted by hand, whereas larger units make use of the truck power winch. In some instances, smaller |

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