The Energy Counter is a block added by IC2 Nuclear Control, which acts like an Energy Unit (EU) cable or wire. By default, the Energy Counter can only handle 32 EU/t, but it can be upgraded with Transformer Upgrades within its GUI. When energy goes through the counter, the Energy Counter counts that amount of energy that has flowed through it.
The counter can be reset by clicking the Reset button within the GUI. The Counter can monitored via a Counter Sensor Location Card.