9403 output pull up

[galanm]

I have a 9403 that I'm using to provide a pulse stream to a Kollmorgen P70530-SDN step motor drive. A scope on the outputs show a strong 5V pulse but when it is connectoed to the input of the drive, the pulses drop to 4V and are not enough to drive the amplifier. What is the best way to pull those back up to 5V? I have attached the Kollmorgen manual page that could address this, but it may or not be applicable for the 9403.

[JoeySpinella]

Hi Galanm,

In the 9403 manual, there is an overcurrent protection built in that is described. When the maximum output current of 64mA (actually 2 mA per channel) is exceeded, the device automatically goes into a high-impedance "safe mode" for 280 ms.

http://www.ni.com/pdf/manuals/374069e.pdf

This device is designed to output digital TTL logic but not to power a stepper motor. What current draw does your motor require? I believe for many stepper motors the requirement is on the order of 500 mA/step.

I found the discussion in this document to be helpful in understanding the amperage and wiring of stepper motors:

http://www.robotoid.com/bonus-chapters/rbb2-ch19-Working_with_Stepper_Motors.pdf

Top of page 284.

In order to power a stepper motor, you will need something like this:

http://sine.ni.com/nips/cds/view/p/lang/en/nid/206346