text: <s>[INST] Ultra 100 I replaced a Ultra 100 drive (firmware 1.36) with another Ultra 100 drive (firmware 1.37) and keep getting a e-stop condition on the Sercos motion control card in the slc500. Put the old drive back in and the fault went away. Question...do the firmware versions have to be the same? I downloaded all the parameters from the old drive to the new drive with no problem. Or is something wrong harware wise with the new drive (the new drive is used but was checked out for good condition. [/INST] First off this is not a SERCOs system. Neither the SLC nor the Ultra100 support SERCOs. I am guessing that this is a HSRV servo control card for the SLC. The E-Stop condition you are getting is coming from the hardwire E-Stop input on the HSRV card. This sometimes has a drive fault contact in series with other E-Stop devices. If you did not get any warnings when downloading, then it should be fine to go from 1.36 to 1.37 so I would check the relay output of the drive. You could also check the settings for the IO between the two drives to make sure they match after the download was completed. \\n </s>