[20:15:07] [Client thread/ERROR]:
 CCL has caught an exception whilst rendering a block
  BlockPos:      x:4593, y:63, z:5553
  Block Class:   class gregtech.common.pipelike.cable.BlockCable
  Registry Name: gregtech:cable
  Metadata:      0
  State:         gregtech:cable
 Tile at position
  Tile Class:    class gregtech.common.pipelike.cable.tile.TileEntityCable
  Tile Id:       gregtech:cable
  Tile NBT:      null
You can turn off player messages in the CCL config file.

java.lang.NullPointerException: null
	at gregtech.common.render.CableRenderer.renderCableBlock(CableRenderer.java:140) ~[CableRenderer.class:?]
	at gregtech.common.render.CableRenderer.renderBlock(CableRenderer.java:134) ~[CableRenderer.class:?]
	at codechicken.lib.render.block.BlockRenderingRegistry.renderBlock(BlockRenderingRegistry.java:94) ~[BlockRenderingRegistry.class:?]
	at codechicken.lib.render.block.CCBlockRendererDispatcher.func_175018_a(CCBlockRendererDispatcher.java:69) [CCBlockRendererDispatcher.class:?]
	at net.minecraft.client.renderer.chunk.RenderChunk.func_178581_b(RenderChunk.java:200) [bxr.class:?]
	at net.minecraft.client.renderer.chunk.ChunkRenderWorker.func_178474_a(SourceFile:100) [bxn.class:?]
	at net.minecraft.client.renderer.chunk.ChunkRenderDispatcher.func_178505_b(ChunkRenderDispatcher.java:172) [bxm.class:?]
	at net.minecraft.client.renderer.RenderGlobal.func_174970_a(RenderGlobal.java:976) [buy.class:?]
	at net.minecraft.client.renderer.EntityRenderer.func_175068_a(EntityRenderer.java:1316) [buq.class:?]
	at net.minecraft.client.renderer.EntityRenderer.func_78471_a(EntityRenderer.java:1259) [buq.class:?]
	at net.minecraft.client.renderer.EntityRenderer.func_181560_a(EntityRenderer.java:1062) [buq.class:?]
	at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:1119) [bib.class:?]
	at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:398) [bib.class:?]
	at net.minecraft.client.main.Main.main(SourceFile:123) [Main.class:?]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_51]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_51]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_51]
	at java.lang.reflect.Method.invoke(Method.java:497) ~[?:1.8.0_51]
	at net.minecraft.launchwrapper.Launch.launch(Launch.java:135) [launchwrapper-1.12.jar:?]
	at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.12.jar:?]
[20:15:07] [Client thread/INFO]: [CHAT] CCL Caught an exception rendering a block. See the log for info.