I think you've misunderstood Derick. Of course you can leave this if wanted instead of the original Giant one, but it's not the right way to do things. Best practice is to swap only the cellpack of 20 cells, using all of the original Giant components, including it's fuse, and it's that which I intend. The components with the Powacycle battery are designed for the usage of the Powacycle bike and not matched to the Giant one. I have in fact made that clear in the instructions on my website, quoted below:
"Basically, it's just the cell pack block of cells that get changed, and any sensors, additional terminal strips with measuring functions etc, must be transferred to the new cellpack."
In other words, don't use any of the Powacycle parts except the 20 cell pack.
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