Never heard of that default IP address for M-series NSP.
The IP address of the management port is set during the initial configuration of the sensor.
Anyways, if you could connect via console to the device, you could execute the command "show" to see the sensor's IP address.
Use this then for SSH connection. If you don't see any IP address, then I guess you have to re-do the initial config.
What ip address for ssh connection for management port is default after resetconfig ?
After resetting the sensor to factory default, you would be required to re-do the initial configuration.
In here you have to set your mgmt port network settings.