The X-10 security RF protocol differs from the one they use for lights and appliances but both are based on the NEC IR protocol. You can see details here...
[Link: mbx-usa.com]The security codes cannot be sent with standard X-10 RF transmitters but only with their security remotes.
If within RF range (poor with most X-10 RF), I can disarm any X-10 RF security console in under 30 seconds. In this case, I think
security is a misnomer.