Please refer this script to monitor the RAM Usage
It will send you an alert if the RAM usage exceeds the defined Threshold value.
Along with the details of the Top 5 RAM consuming processes.
1.Threshold_Value - Value of the RAM usage level in percentage
2. oper - Comparision operator like ">=" ,"<=" ,">" ,"<"
Threshold_Value = 70
oper = ">="
if the RAM Usage level reaches the Theshold limit, the alert will send to you