Ping feature

I am setting up the Ping Notification feature and need some insight into how it works.  

My understanding is that it pings the selected device every 5 seconds.  Is this a consistent 5 seconds for as long as i have the device added to the ping feature?  I don't know that i need it to ping every 5 seconds (can this be changed)

300ms for 1 minute, i dont understand this... how often is it checking the device?

Any help would be appreciated,

Thanks.