Yeah, if you're trying to charge 5amps using a 5amp power supply, you won't make it, you'll wind up with less than 5amp.

Possible exception is that 5amp PS that HC sells for the Accucel-6. Thats been tested to 6.9amps and can power a charger at 5amps. This looks like a laptop power supply and needs the cord from PS to the wall (it doesn't come with it).