1.If one of the agent stopped sending event then how can we find it through SSIM console?
2.How to find EPS pre device?
I guess there will be one Alerting incident will get created, when the appliance doesnot receive any event in the past X seconds from the agent Y.
You may modify that rule as per your needs.
To monitor EPS, you can go into visualiser, the table view.
Each agent/sensors is listed with its EPS.
You can increase the frequency by changing the Event Statistic value in the SESA Agent properties.