I wanted the fluorescents to be controlled also, but connecting them to the TRIAC output of the SceneMaster is risky. I therefore chose to add a relay to the SceneMaster. The coil is wired to 'Load 4', and its output is connected to the unused contact on the barrier strip on the back of the SceneMaster. The relay is a four pole, double throw, and fits inside the SceneMaster. The whole package is quite tidy and self-contained. Three poles of the relay are used in parallel to share the current and to provide redundant contacts. The fourth one is left for a spare contact in case the other three fail. If that point comes I can then temporarily wire to the fourth one to get the circuit operational again, buying me some time to think up a long term solution. In addition to three poles sharing the current, I added an MOV (Metal Oxide Varistor) surge suppressor across the relay contacts.
One operational restraint is that this circuit is not allowed to be dimmed. When the 'Load 4' circuit is dimmed, the relay buzzes loudly in the transition range between bright and dark. When this occurs, the fluorescent lights (240 Watts in all) do not light. Time will tell if this is an issue.
The Control Panel for the PCS SceneMaster.
Unlike standard X-10 wall switches, the SceneMaster does not have a control pushbutton built into it. In order to have non X-10 control, one needs to purchase 'slave switches'. Since I needed about six of these at a cost of about $20 each, I realize that non X-10 control could get expensive. For that reason I investigated building the slave switches myself. Based on the user manual of the Scenemaster I speculated the following schematic could be used instead of the slave switch.
Testing showed that this circuit does indeed work. I found that the half watt resistor could be as high as 500K, but I decided that 100K provided a good compromise between operational margin and a safe current limit. The buttons used were round and square pushbuttons from TechAmerica Inc for about $2 each. Apart from their low cost, these switches were chosen because they fit into the hole of a standard wall plate. I could then reuse the existing wall plates, which already match the decor of the home.
The actual unit mounts on the wall behind the control panel, which happens to be the garage of my home. The large box above the PCS unit is the alcove that houses my Home Automation Computer.
Detail of the wiring behind the control panel. Note the following: