To calibrate a photocell for use with the SwitchPAK (SPAK), connect the photocell to the switchpak analog inputs. Then, while it is the desired light level out, click on menu, scroll down to Diagnostics, and then select photocell status.
This will tell you what light level the cell is currently reading. If this is as bright as it gets in its location, you need to set the device to this calibration. Click the set button - the Mac level will change to the current setting.
Now, cover up the photocell eye. Give it a few moments, then check the photcell status screen again. It should now be reading a light level significantly lower than the one prior, and a low percentage. Remember this number - it is how we will set the photocell settings under inputs.
Hit your back button out to the main menu. Now, press menu, go to Inputs, and press the photocell button on the panel. Click edit, select the relays you want affected by the photocell. Next, set the percentage for "on" to be < a number 5% higher than the number we read when the photocell was covered. Set the "off" to a number 15% higher than that number.
Your device should now be set.