Stepper Motor Power

I am assembling an Acro 1510 unit to be used as a pen plotter. Everything has been going fairly smoothly but I have an issue with the stepper motor I will be using as part of my z-axis pen lifter. Everything is wired and I get z-axis movement with it but within a minute it began to run super hot, to the point I could smell it and became too hot to even touch. The stepper motor came with a 4-pin connector hooked up to it. I added an open-builds connection and 4 conductor wire to it, matching the colors (except black became yellow):



ran that back to my black box and plugged it into the top 'z-motor' port:



So am I wired correctly? It seems like I am as I am able to get z-axis movement but seems I'm getting way too much power. Is there a way to reduce the power draw or should I be using a different connection? Or is my stepper motor possibly just defective?

As a back up, if there's an alternate pen-lifter assembly that's more suited for someone with basic knowledge please let me know. The Open Builds videos have been great to this point but would love some help crossing the finish line!

Thanks in advance!

 

Alex, thanks for the response, much appreciated. Will try adjusting the z-current.

Here is a link to the motor online and below is the spec sheet:

 

Will do, thanks Peter