Configure Netscan to ignore powered off VM's

Hi there, 

I have a netscan configured to import VM's from VMWware. However, it always imports all VM's including those that are powered off. This causes problems when critical alert are getting triggered on servers we know we have powered off. 

Is there a way to configure the netscan to filter out those VM's which are powered off? I was previously given one suggestion to use tags but that is not very useful as we would need to keep changing the tag every time if we wanted to monitor that VM. 

Any tips?

Thanks!