1st is the regulator giving the correct value at the higher setting? If it is, use the regulator. If it isn't, try setting manually. This could be problematic if the power supply is really limited to 1100 amps. It sounds like it isn't. So... If we must excede what we can get from the power supply, I recommend you call in the power supply expert(s) i.e. Jack and or tech on call.