The Minecraft wiki has articles on that, so I recommend you go and check those out. In order to start with Tekkit, you need to survive a few nights. To change, voltages, one must use a Transformer, which changes the packet size of a current, but not the actual amount of electricity. There are 5 Voltages, each with their own respective cable.

So, voltage needs to be managed carefully. Voltage (UV,LV,MV,HV,EV): Like the real world, too much electricity can implode a system.

There are 5 Packets: UV, which goes up to 5 EU/t and uses Ultra-Low-Current Cable, LV, which goes up to 32 EU/t and uses Copper Cables, MV, which goes up to 128 EU/t and uses Gold Cables, HV, which goes up to 512 EU/t and uses Glass Fibre Cables, and EV, which goes up to 2048 EU/t and uses HV Cables. Packets can be changed with a Transformer. Packets (p): Packets are the measurement for voltage.Like real electricity, too much EU causes an explosion! EU-in-realtime is measured in EU/t (Electrical Units/Tick). Machines both produce and use it, and even some armor, tools, and weapons. Electrical Units (EU) : EU is the measurement of electricity in IndustrialCraft 2.Understanding Chunks is very crucial when building large-scale buildings or Nuclear Reactors. A player inside a Chunk will load the Chunk: a player very far away from a Chunk will leave it unloaded. Each Chunk is a 16 by 16 by 256 rectangle. Chunk : Chunks are segments of Minecraft worlds.It is used in most measurements, such as EU/t, MJ/t etc. It is the max a Block can Update, and is constantly used opposed to seconds (20t=1s). Tick (t): Ticks are the measurement of the Minecraft world.IC2 : The abbrieviation of IndustrialCraft2.Though, to understand IC2, you need to understand a few concepts: The IndustrialCraft2 mod is a great place to begin the Tekkit experience, and a major reason for this is the Macerator. 15.3 Upgrades! (Chambers, Advanced Cooling).15.1 Basic Reactor Mechanics (Heat and Cooling).

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