Ah! So (most typically) the only time you really need 4 wires is between service panels that might be called on to provide both 120 and 240v branch circuits or when running to devices that need both 120 and 240 (like maybe some contraption with a 240v contactor controlled by 120v?).
Last...
You guys are awsome.
I had been thinking of these as taps but wasn't sure if I had the right context. I'm much smarter now.
After posting, I came to think that I'd need to do what pattenp (and others) proposed which would have worked but been a drag. However, the winner of this...
I hope this isn't aleady covered somewhere. I searched but couldn't quite find what I was looking for.
I have a crowded subpanel with room for one more 2 pole circuit breaker. I want to install two 240v 3200watt Infrared heaters.
My thought is to run 8/3 from a single 40Amp CB to a junction...