Emerson E2 - Manual (Page 173)

Lighting Schedules Software Overview • 11 - 31
setpoints, and overrides the schedule as the real-time light-
ing conditions warrant. As a result, the light level sensor
and schedule both work to provide adequate light when needed AND saving energy by keeping lights OFF when
they are not necessary.
11.10.2 Functions of the Lighting Schedule Application
Figure 11-19 shows a flowchart diagram of the Light-
ing Schedule application and the eight cells that work
together to control the lights. A description of each cell
and the functions they perform are given below.
11.10.3 Control Method Select
Control Select determines whether the Multi-Logic
Combiner is used or the Light Level Interface and Sched-
ule Interface are used for Lighting Control. When Use Alt
Control is set to Yes, the Light Level Interface and Sched-
ule Interface combination strategies are disabled and are
not visible. When Use Alt Control is set to No, the Multi-
Logic Combiner matrix is disabled and not visible.
11.10.4 Standard Control
Standard control comprises Light Level Interface and
Schedule Interface strategies.
11.10.4.1 The Light Level Interface Cell
(LLEV INTERFACE)
The Light Level Interface cell of the Lighting Schedule
application translates the value of the light level sensor
into an ON or OFF command by comparing the analog
light level to a set of Cut In/Cut Out setpoints.
From an OFF state, when the light level falls below the
Cut In setpoint, the result of the light level comparison
will be an ON state. When the light level rises above the
cut-out setpoint, the state will transition from ON to OFF.
The ON/OFF state determined by the light level can be
logically combined with LOGIC IN, a digital input from
an input point or another application in E2. The result of
this comparison will be the final ON/OFF light state com-
mand that is sent from the Light Level Interface cell to the
Schedule Interface cell (explained below).
Logical Combination Strategies
There are several different strategies for combining
the light level ON/OFF state with the value of the
LOGIC IN input:
• Logic Only - The cell will read only the
LOGIC IN input and ignore the light level
sensor reading.
• LLEV Only - The cell will read only the light
level sensor and ignore the value of the
LOGIC IN input.
• Both ON/Both OFF - From an output=OFF
Figure 11-19 - Lighting Schedule Module Cell Diagram
Output DV
Proof DV
Proof DV
Light Schedule DV
Lighting Control Module
In Out
Min On/Off
On/Off Delay
Min On/Off
with Delay
DV DV
Desired Value Proof Fail
Delay
Latch Time
Proof
DV DV
Actual Value DV
Logic In DV
Use Alt Sched Comb DV
LLEV In
Logic In
Occup
Out
Comb Type
Alt Comb
LLev
Interface
AV
DV
DV
DV
Use Alt DV
Invert Output DV
Cutin/out SPs
Use Alt LLEV Comb DV
Out
Events
Active Days
Basic Sched
DV DV Extern Sched
Use Ext Sched
Light Level LLEV AV
LLEV Occup DV
Bypass DV
Logic In
Sched In
Use Alt
Out
Comb Type
Alt Comb
Schedif
DV
DV
DV
DV
Invert Output DV
Sunset Today DV
Offset
Control
Rise/Set Offset
Multi Logic
Combiner
Use Alt Comb DV
Logic1
Logic2
Logic3
Logic4
Use Alt
Out
Control
Method
Select
Use Alt Control