Emerson E2 operation manual Basic Schedule Cell, Min ON/OFF Cell, Proof Cell, Offset Solar Control

TIP: Activating the Use Alt Control parameter is the only way to use the Solar Calculation Control method for Lighting Control.

11.10.5.2 Offset Solar Control

The Offset Solar Control cell of the Lighting Schedule application uses the Sunrise Offset and Sunset Offset parameters to determine how many minutes before or after sunrise the sun is considered to be risen, or how many minutes before or after sunset the sun is considered to be set. The resulting offset for sunrise and sunset is used by Lighting Control in its logical equations for the Solar state.

A positive value is entered if adding to the sunrise time, and a negative value entered if offsetting the sunrise to an earlier time. For example, if the user wanted to turn the lights OFF one hour before sunrise, Sunrise Offset would be set to -60, and if the user wanted to turn the lights ON 45 minutes after sunset, Sunset Offset would be set to 45.

11.10.6 The Basic Schedule Cell

The Basic Schedule cell has two main functions:

•If a Time Schedule application is set up in E2 to provide ON/OFF times for the lights, the Basic Schedule cell passes the occupied/ unoccupied state from this time schedule to the Schedule Interface or Multi-Logic Com- biner cell.

•If no Time Schedule application is set up in E2 for light scheduling, the Basic Schedule allows you to configure a schedule for the Lighting Schedule application. This custom schedule will pass along a digital occupied/ unoccupied state to the Schedule Interface or Multi-Logic Combiner cell.

If an external Time Schedule will be used, you will only need to configure the Basic Schedule by linking the schedule output to the input of the Basic Schedule cell and setting the Use External Schedule parameter to “Yes.”

If no external Time Schedule is being used, you may configure a set of schedule events and date ranges to be used by the Lighting Schedule application. Up to 15 ON/ OFF schedule events can be programmed, as well as up to 12 date ranges.

Schedule events and date ranges programmed into the Basic Schedule cell are used only by the Lighting Sched- ule application. If more than one Lighting Control applica- tion will be using the same schedule, it is recommended you configure an external Time Schedule application so you won’t have to re-enter event and date information for each lighting application.

11.10.6.1 Slave Scheduling

If you have an external Time Schedule application pro- viding occupied/unoccupied times, but you want to alter this schedule slightly for the Lighting Schedule applica- tion, you can designate the Basic Schedule cell’s schedule as a slave schedule.

A slave schedule differs from a master schedule in that its events are relative to the events of a master schedule. A master schedule’s events are absolute times (like 08:00 ON, 23:00 OFF). A slave schedule contains a set of times that are added to or subtracted from its master schedule’s events (like +00:30 ON, -01:00 OFF). As a result, the behavior of the output of the slave schedule is altered slightly from that of the master schedule.

Slave scheduling is most often used in cases where the master schedule represents the occupied/unoccupied times of a building, and slave schedules are used to control loads that need activation or deactivation earlier or later than the occupied/unoccupied times.

11.10.7 The Min ON/OFF Cell

The Minimum ON/OFF cell has three important func- tions:

•It receives the light state requested by the Schedule Interface cell, and applies this state to a set of minimum ON and OFF times. If the requested light state turns ON the lights before the prescribed minimum ON time, or turns OFF the lights before the prescribed minimum OFF time, the Minimum ON/OFF cell will delay the command until the mini- mum ON or minimum OFF time has elapsed.

•If ON and OFF delays are specified, the cell delays ON/OFF commands it receives from the Schedule Interface cell.

•It processes commands for manual bypass- ing of the light state. When the Bypass input is any value other than NONE, the cell ignores the light state command input, all minimum ON/OFF times, and all ON/OFF delays, and bypasses the light state to the digital value of the Bypass input.

The digital output of this cell controls the I/O board output point that activates and deactivates the lights.

11.10.8 The Proof Cell

The Proof cell verifies that the lights are turning ON and OFF as commanded by the Lighting Schedule applica- tion. The Proof cell compares the digital command sent to the I/O output that controls the lights with a digital input from a proof checking device (like a digital light level sen- sor). If the two inputs are not equal for an amount of time

Lighting Schedules Software Overview • 11-33