Sunday morning at 4:16 am the company was dispatched for a transformer fire inside the PECO power substation on Route 322 in East Bradford Twp., when the units arrived they discovered a small fire on a piece of equipment inside the fenced area. Crews stood by until PECO arrived to shut down power to the equipment, while there, the dispatch center advised of a second call for an Automatic Fire Alarm in the Brandywine Green section of West Bradford Twp, the two engines assigned to the transformer fire responded to the fire alarm and found it to be an activation due to the power outage, while Chief 39 remained at the PECO substation until PECO extinguished the equipment fire. The dispatch center advised of a third call on Sawmill Road. Chief 39 and Engine 39-3 made the response to Sawmill Road for what was reported as a transformer and after clearing the fire alarm Engine 39-1 responded to the lower end of Sawmill Road to standby as well. Units arrived to find a large fire burning in the wooded area however could not access it because of the live power lines down. Crews stood by on Sawmill Road for approximately 2 1/2 hours waiting for PECO to arrive before we could check to see what was burning. Once PECO arrived and power was confirmed off, we were able to access the site and found that a high voltage transmission line broke and fell to the ground igniting the underbrush around it. Crews wet the area to confirm the fire was out and the area was cool, even though the snow and rain had extinguished most of the fire. Units cleared at approximately 7:45 am.