PING SMS also called Silent SMS ,it allowing the user to
send a message to another mobile phone without the knowledge of the recipient.
The message is rejected by the recipient mobile and leaves no trace.
Silent SMS were initially meant to allow operators to acknowledge whether a mobile phone was switched on and test the Network without advising the user.
Just need change SMS text with fix format <PING> , or check button 'PING SMS'
Query Reports->Status Report to get the delivery report. If the message is delivered to destination phone number, the status filed will show 'Sent(0)'