It is the same current output as that of the 734x or 745x controller you are using, which in any case would be +/-10v, +/-5 mA. If you are using a 733x controller, the signal is not connected. Unless your Dc motor is supper small, I doube you will be able to drive it with so little current. I think what you need is a servo drive to accomplish this. The MID 765x drives are the an example of this type of drive, though you can find some othe options in or drive advisor at:
http://www.ni.com/devzone/advisors/motion/driveadvisor.htm