When I first started using the charger and turned the charger on and then connected, I was getting an error and charger would not allow charging to proceed. Hyperion puts big warning in the "manual" about not balancing while charging - telling you that you do so at your own risk, so I wanted to charge and balance if any way possible.

Just for S&G, I just tried the other way - turned the charger on, connect the power, then balancer wiring. Guess what? Works fine! This did not work for me a week or so ago and I was so puzzled over why, I pulled the tape off the 2nd I a123 pack I built to double check the wiring - even more puzzling, it was correct. When I connected everything with the charger off, everything worked - balanced while charging.

The only thing I can think of is this was before I soldered a male deans on the supplied connector and I was sharing a connector with my Ice charger. I see the manual explicitly says "Always connect the output cable set to the charger first, then battery". See halfway down on 2nd page where it starts with the bold Note: I guess when I was still sharing the output connector with my other charger, I was not doing this. Now that my 601i has its own output connector, it stays plugged in so won't be done in the wrong order.

So, in answer to your question - no, you don't have to plug in then turn the charger on. The one thing you apparently need to do is to connect the output cable to the set to the charger, then the battery, then connect the balance connector. Sorry I freaked you out dude, but your question cleared up the mystery as to why I was getting that error the way I apparently connected mine.

Moral to this story - put a connector on the supplied output cable setas soon as you open the charger, install it immediately so you'll never connect things in the wrong order.