test

cell = peripheral.wrap("left")

while true do
  local energy
  energy = cell.getEnergyStored("north")
  print (energy)
  if energy > 4000000 then
    redstone.setOutput("back",false)
    sleep(1)
  end
  if energy < 100000 then
    redstone.setOutput("back",true)
    sleep(1)
  end
end