DC Motor draws more current?

[AmazingTrans 0]

Gurus, I have a question that I couldn't answer, other engineer in the plants couldn't answer, neither can AB explain why? Currently, there is a upgrading project going on. From a Fincor dc drive, to powerflex Dc drive. They are both 200 HP. The problem here is this. When the fincor drive was running, the amount of current % / torque value the motor draws is only 75%, but by using the powerflex dc drive, it draws about 135% which causes overload to the motor. Does anybody have any idea what would cause this? The motor is: RPM = 1750/2400 (running at base speed) Varm = 500V Iarm =320V Ifld = 8-4.6/4-2.3 (The drive is setup at 4Amps at 300V) Thanks, AT