Hopefully someone can assist with this particular question. I have searched the web and have been unable to find anything thus far so I figured I would post here and hopefully someone may have the knowledge to answer. I need to replace a siemens drive motor on a machine, the original unit was a 1FT6044-4AF71-4EH1 and was later replaced with a 1FT6044-4AF71-4EH6. I want to know what the difference in the two motors is since the only difference in the number is 4EH1 and 4EH6.