Unfortunately, machines exploding and cables melting are not implemented yet because the energy net is still in development. The temporary system is a lossless, limitless, balance-less, and transformer-less contingency because mechanics like loss and EU details are also not implemented yet. This means we have no mechanics to calculate: an insulated tin wire would do the trick. I'm sure the devs will post a big, Biomes O' Plenty style warning when it's time for machines to explode and cables to melt again, and we'll write it up in the wiki as soon as those features are back.
If you just want to make sure the EU/t going through a cable is within the range on the cable's tooltip, you can try seeing if transformers in step-down mode work. I don't use them myself for reasons listed above, but they seem like they should take input up to the highest value in their tooltip from the special-textured side (five dots) and somehow output a maximum of one current at the minimum EU/t in the tooltip for each output side (one dot). I haven't run tests yet, but I should and will probably post back here when I do, for closure.
Do your RTGs have 5 or 6 Slots? the ones with 6 Slots do 32 EU/t.
You'd better use an EU-Reader for more accurate output.
Why would you ever have a picture of that? 
Why would you ever have a picture of that?
You don't get it? Google an origin of this picture, and after that read topic name carefully. 
Wow. Remind me to never search witch cable on google.
I first noticed the typo about HV being 2048 EU/t ... damn me.
