Harold_V wrote: ↑
Sat Nov 02, 2019 1:38 am
In regards to the home run grounds we were discussing, one of the benefits is that it's harder to lose everything. If common ground is, somehow, interrupted, everything would shut down. I can only assume that the intention of the engineers was to avoid such a thing. Better to lose one feature than all of them.
When an engineer designs anything, he has to design to the environment, and to say that the underground mining environment is harsh, is a major understatement, and where the phrase "well duh!" came from.
Generally speaking, besides being dark, you have equipment running around in confined areas, and it inevitably is bouncing off solid rock here & there. They drive through muck, water, over rocks and big rocks, and mud, to a point, where you can no longer tell what color they were. Miners & mechanics climb all over it, an although most are not meant to be work platforms, they are used for one, inevitably causing them to get rocks bounced off all over them. (Barring down loose of the top of a machine is common.)
Most mines are wet, some, extremely wet where it rains all the time, and many make Miami seem like the Mojave. Add to that, that many are mining sulfide deposits. Now, you have acidic water. You can watch copper wires turn green, and get fuzzy.
A lot of mines are hot, including extremely hot. That doesn't help a bit.
Some are cold, and to keep the mine water supply from freezing, they add salt to the water. Enter another problem.
So, basically, what makes sense and works on your Buick, Is not necessarily going to work on an UG mine vehicle, nor be a benefit.
Most electrical failures, are at terminations, and also, wires, so on UG equipment, if you add a home ground run to the real lights, you have just doubled the points and area of failures. You have also added to the complexity of the system, making it harder to troubleshoot. Some of those wires are in places a body can't get to.
I have pulled out wires on equipment, that had more butt-splices from repairs, than wire. Any UG mechanic that has been around a year or two, will tell you the same thing. Plugs, are routinely wired around, as the plug and/or sockets in them have failed.
Underground Mining Equipment is the most abused equipment on the planet.....other than a Humvee with an RPG coming at it.
This changes the design criteria, and again, what would be a benefit on a Yawn Deer, or even a 994 or other surface machine, is the opposite on most machines heading under the earth.
Today's solutions are tomorrow's problems.