The T 282 mining truck from Liebherr Mining Equipment stands almost 25-ft tall, is 47.5-ft long, and almost 30-ft wide, with a capacity of 400 tons. An ac electric drive powers the two-axle truck.
The T 282 mining truck from Liebherr Mining Equipment stands almost 25-ft tall, is 47.5-ft long, and almost 30-ft wide, with a capacity of 400 tons. An ac electric drive powers the two-axle truck.
 
Power-distribution units from E-T-A plug in behind the driver's seat and hold 28 thermal-type circuit breakers.
Power-distribution units from E-T-A plug in behind the driver's seat and hold 28 thermal-type circuit breakers.
 
Units use E-T-A's 482-Series thermal circuit breakers rated for 10-g shock vibration from 10 to 2,000 Hz.
Units use E-T-A's 482-Series thermal circuit breakers rated for 10-g shock vibration from 10 to 2,000 Hz.

Power-distribution units from E-T-A Circuit Breakers, Mount Prospect, Ill. (www.etacbe.com), cut nearly three weeks off the production of large mining trucks. The PDUs go inside T 282, two-axle, electric-drive haul trucks made by Liebherr Mining Equipment, Newport News, Va. (www.liebherr.com).The original design mounted 20 thermal circuit breakers in a bulky dashboard unit, a process that took about three weeks to complete.

In contrast, the PDUs install in one day with a multisocketed connector that mates with a connector in the truck wiring behind the driver seat. Added space afforded by the design let eight more circuit breakers be installed for a total of 28. The breakers protect truck electrical systems including computer instrumentation, lighting systems, and cabin components, even a CD player.

-- Miles Budimir