Hey guys,
Here is my latest addition to "baby George".?
I melted the previous high amp pass thru by putting way to much current thru it.? The previous unit was made of 9 each 1/4" bolts passing thru Scotch Weld 2216 epoxy.? Turns out 1/4" rods are rated for about 120 amps at best and when you pass 360 amps thru them they get really hot.? I guess I missed the part about serial current being less than parallel current.? Who knew that 90 amps x 12 volts is not the same thing as 360 amps at 3 volts.? It was all bad from there. ? But I choose to move on and not live in the past.
The new pass thru's (now there are 2 of them) are made with 3/8" rods.? The epoxy and 1/2" thick acrylic spacer plate are the same.? I once again discovered that 1/8" o-rings in square o-ring grooves are the answer to making vacuum tight seals.? Note that 1/4" o-rings in curved grooves are not the answer to anything.?
Just thought you would like to see a poor boy's solution to high amperage pass thru of the chamber wall.? The 360 amps is needed for the 4 each tungsten emitters in parallel.? With 9 separate coil stations I need 9 separate pass thru.? I do the switching outside the chamber and feed the full current to each quad emitter station.? It is a rats nest of fiberglass sock shielded welding cable inside the chamber but them tungsten coils do get hot quick now.? No more waiting for the the slow coil to heat up.? They all get to hot fast and I am no where near the edge of the 12kw supply.?
Drew in sunny Florida
