Thist article outlines the basic steps that you'll need to do. It's specifc to Cisco IOS but the process is the same.
1. Place the firmware image onto a TFTP/SCP server. This can be the TFTP/SCP server that comes with NCM or your own.
2. Create a script for downloading and deploying the firmware. (These would be the exact commands that you'd on on your switch via SSH to manually upgrade the firmware)
3. Schedule a job to execute the script at the time which suits you. Or run it adhoc by selecting the switch and choosing 'Execute Script.'
Thank you very much for your response.