Timers
This is the dialogue to set up timer functions. There are four general timers available. Before timers can be used, appropriate hardware has to be attached to the Phidget 8/8/8 output ports 0-3 or to the Phidget 0/16/16/ output ports 4-7. Phidgets cannot drive any high power device directly. See Building a HydroHomeSoft Hydroponics System for more information on appropriate devices. Timers are generally used for turning lights, pumps, fans etc. on and off at preset times and/or with intermittent cycles.
Select the timer to be set in the Timer dropdown list. A more meaningful Name other than the default Timerxx can be entered. There are three radio buttons on the top right having the following functions:
General – the timer functions independently
Channel – the timer is associated with a Schedule channel
Disabled – the timer is not active
Below the Timer selection is Startup delay. This is important for HID lights and equipment with compressors. These devices can be damaged if turned on again too soon after they shut down. The cool down period depends on the type of equipment. The Startup Delay selected is applied to the beginning of each new timer cycle, on a restart after the Emergency Stop button is pressed, and whenever the timer parameters are changed. PLEASE NOTE THAT THIS DELAY PERIOD IS NOT AVAILABLE IF TIMER ON CYCLES IS GREATER THAN ONE.
Provided the timer is not linked to a Channel, two schedules can be defined: Primary and Secondary. The Primary schedule is usually assigned to the photoperiod or light on period. An example would be the flood periods for an ebb/flow setup. The Secondary schedule is designed to provide, for example, supplementary flooding during the dark period. The Secondary cycles are evenly distributed over the period not covered by the Primary schedule. The Secondary schedule always begins with an OFF state.
The Start time and Stop time areas each have three choices.
Sunrise – use the calculated sunrise time for the location
Sunset – use the calculated sunset time for the location
Specific time – enter any time from 00:00 to 23:59
Timer cycles is used to establish the ON/OFF cycle regime. If more than one cycle is required, an ON time can be set and the OFF time will be automatically calculated. If either sunrise or sunset is selected for start and/or stop times, the OFF time will be recalculated daily. To provide continuous cycles with specific ON and OFF times, select 999 in ON Cycles.
Clicking on Apply will implement all changes immediately. If changes are made for a General timer with a Startup Delay, the delay will be applied at the next Start time or immediately if the timer is currently ON. Similarly, clicking on OK will apply the changes immediately and close the Timers dialog.
Clicking on Cancel discards all changes.
