I have a screen shot.

https://www.flickr.com/photos/126613374@N08/15389342084/

For some reason I don't know why. The wires for BC don't stop working. When a try and send a signal from point A to point B. The only way to fix this is too bust the pipe and wire and replace them. Then soon after it does it again. So I'm confused by the reason why this doesn't work like it did before.
Ice

Is that break between chunks? It happend to me with Red power when I went into the nether and got back, wires in loaded chunks (by chunk loader) were working and pipes in unloaded chunks were off.

None of the above. This wire goes from one gate the the next gate. The only machine I use is the BC pump. The problem I have is I have broilers hooked up to the wires. and if the wires fail and a broiler needs water. It could blow.

I had a similar situation when connected to Forestry machines (release version... Dev version fixed it). Do you have the same issue when using ONLY vanilla or BuildCraft machines?