EchoTime is a read-only Cardinal property that indicates the number of milliseconds required to send and receive data using the Echo method. Use EchoTime to determine when there may be problems with the network or connection. 

EchoTime is calculated in the Echo method using GetTickCount and GetTickDiff, and represents the elapsed milliseconds from the start of the echo request until completion of the echo response. EchoTime is adjusted to reflect situations where the ending time reverts to a 0 (zero) value after the Echo transmission has been started.

TIdEcho.Echo GetTickCount GetTickDiff