Photocell Sensor (Model PHO-1)

The Photocell sensor allows the Plant Pro controller to operate based
on the presence of natural (sun) light.  There are three user selectable
operating modes:

1. Natural Duration Mode: In this photocell mode the Plant Pro is controlled
by sunrise and sunset instead of its internal time clock.  Artificial lighting
plugged into the Plant Pro goes on and off at the same time as natural lighting.
This mode also allows the Plant Pro to function when the grower uses natural
lighting only.

2. Fixed Duration Mode: Artificial light comes on at sunrise for a period of time
set by the user.

3. Total Duration Mode: Set the total time you wish the garden to have light.
If the of natural light is insufficient, the artificial lighting will come on at sunset
to the make up the difference.

The Photocell Sensor mounting flanges allow it to be placed against a window
facing outwards towards the sun (or natural light).

The Photocell Sensor uses an arbitrary scale of 1 to 100 units of light intensity 
(not Lux or Lumens). It can also be used to measure the relative intensity of light
around the garden for best lamp placement.

For complete details on  Photocell Mode operation, see the Plant Pro instruction
manual.