Automating outside lights on house using X10 PRO

We've pretty much maxed out our Lutron RadioRa system and I still wanted to control a few more lights on a timer (like the back yard flood, lights on the side of the garage etc). The XPS3 is rated to control flourescent lights (unlike the Lutron).

I still prefer the Lutron for the main house, as it can be grouped into scenes with various lighting levels and fades gently on and off, in addition to being completely silent. On the other hand, the X10 switches cost about 10% of Lutron RadioRa's. It should be noted on the X10 XPS3 that a click can be heard (since it contains a relay) when it is activated. We used X10 PRO (as opposed to X10) as they are UL listed.

X10 works by sending commands over the AC line of your house. We originally were going to have our Honeywell Vista 20P control a few X10 switches, but never got entirely comfortable interfacing logic level circuitry to the AC line. Thus we ended up buying a little alarm clock like device that they sell to get us going (MT13) that puts the control signals onto the AC line.

We bought these components from http://www.thehomeautomationstore.com/x10-pro.html

XPS3 Decorator Wall X10PRO-XPS3 1 14.99

XPSS Decorator Companion X10PRO-XPSS 1 9.99

MT13A 64-Event LCD Mini X10-MT13A 1 24.99

The wiring was a little confusing, as they need the neutral wire to be present. You also need to be able to identify which black wire is hot in your wall boxes. I have attached a diagram of how our system is wired. Has worked reliably over the last few days, and the MT13 is simple to program.

Eventually we may revert to using the Honeywell to control the timing instead of the MT13, as they also sell a contact closure input device (e.g. PSC01) that we could interface to one of our relays in the alarm system (thus ensuring electrical isolation). For now this works fine however, but I'd like one less device to program if possible. Kim has the programming down on the Honeywell system (she programs our lights when going on a trip to make it look like we are home).

Hope this helps someone.