Universal Devices ISY-994i Series, User Manual

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This slow-dim-to-off is a technique I use widely where there are motion sensors/timers
turning lights off. In my master bedroom and ensuite I don't use motion sensors. Rather,
there is a KeypadLinc in a pedestal on either side of the bed. Each has a button which
causes both the lamp on the corresponding side of the bed, and the ensuite lights to do a
slow fade up which is easy on the eyes in a dark room, to a low level sufficient for the
purpose at hand but not bright enough to wake someone.
Next, we should give some thought to what occurs following a power interruption. Since
ISY cannot poll the status of RF devices (motion sensor, door contact), should it default to
assuming the door is open or closed?
In the case of an interior bathroom, if the power fails while the bathroom is occupied and
the door is closed, the occupant will likely open the door since there will be no light. During
a power failure, should someone enter the bathroom it is unlikely he would shut the door,
as there would be no light. So, either way, when the power returns it is quite likely the door
will be open.
However, once power is restored and ISY reboots, it can take ISY five minutes to query the
INSTEON network in a modest installation and much longer in a large installation. During
that time someone may very well enter and close the door. Clearly it is safer to assume the
door is closed, since that will provide the longer timeout period before shutting off the
light. The downside is that if someone enters, thereby triggering the motion sensor, and
then leaves without having ever shut the door and then opened it, the lights/fan will take
much longer to time out than is necessary. This condition will persist until the door is
closed and opened.
As it turns out, when a device status is unknown, as in the case of RF devices following
reboot, ISY defaults the status to Off with regards to programs. So, in program 10 the door
status will default to closed.