Does not the Hartke have a 6.2 A fuse in the sled next to the IEC input? If so, the rating of the power lead fuse should be irrelevant. If the power lead fuse is blowing but the sled fuse is not, I would suspect you've got either a 5A or 3A fuse in the power leads you're using...
Mark
[quote name='Pow_22' post='1170321' date='Mar 21 2011, 08:13 AM']I recently sold an old amp and accidently gave away my only power lead with it. I bought what i thought was a similar one off ebay (kettle lead style). It only lasted a few goes before the fuse went (i think) as its a sealed socket it got binned. My old man had a spare power lead from a PC that looked the same, so tried that and the same thing happened. Question is, what power lead should i be using for a HA5500?[/quote]