I assume you are trying to synchronize time with an ntp-server. This is how you can configure on sensor CLI :
sensor# configure terminal
sensor(config)# service host
sensor(config-hos)# ntp-option enable
sensor(config-hos-ena)# ntp-servers ip_address key-id key_ID
Later versions of the sensor software also support the unauthenticated option for time synchronization as
qsensor-204(config)# ser host
qsensor-204(config-hos)# ntp-option enabled-ntp-unauthenticated
qsensor-204(config-hos-ena)# ntp-server x.x.x.x
