I found this link over at another forum...thought I'd share it over here: http://hutnyak.com/Trolley/trolleyhistory.html But I think they forgot about the system LeTourneau was building for Anaconda's Berkeley Pit back in the 50's!
so they use them to drive the electric motors on the dumps is what i interpret:beatsme thats a good idea then do they use the motor to drive to the shovel and to dump or what also how do they hook onto the lines? curios is all
Close, what they really did was use the trolley system to power the trucks while out on the haul roads. especially on grades. When the trucks were at the shovel end of the system or at the dump end, they lowered the pantographs and drove like normal. This offered the flexibility of following the moving mining operations without having to constantly re set the trolley lines to meet the operations. Instead, they could set up the lines and use the available electric power to run the trucks at faster speeds than having the on board generator provide the power could on routes that wouldn't change very often. The system used tensioned overhead wires, and retractable pantographs which pushed against the wires and allowed for any variations in the road surface such as dips or humps by simply compressing further, or expanding to reach the wires, so contact was not lost. Hope that clears it up for you a bit more. Brian
Nice piece of trolley history stretch. Wow. I wasn't aware that they've used trolley poles in open mining. Trully. My question is: did they do that out of a search for a more effective way of locomotion or it was all a result of high oil prices and/or massive enviromental protests? Personally I think the whole idea being a bad one. And it looks teribly too. I mean trams and trolley buses in a picturesque city is something. Electric lines and haul-trucks awkard mountings for trolley poles in an open mine, now that's totally out of place.:ban