©2025 Copeland LP.
026-1803 R13 Supervisor I&O User Guide 9 - 24
For example, suppose a master schedule is set up to be ON at
8 a.m. and OFF at 9 p.m. every day of the week, and you wish
to set up a slave schedule so that its output comes ON 15
minutes before the master comes ON and OFF 15 minutes
after the master goes OFF. To do this, you would set up the
slave schedule to come ON at -00:15 and OFF at +00:15
every day of the week. The slave schedule will automatically
determine the correct ON and OFF times.
Maintenance Schedule Events
Each schedule may also be given up to three pairs of
maintenance schedule events. These events start and end at
specific days and times and do not continue past those dates
(in other words, maintenance events cannot be made to
occur weekly or annually).
Overlapping
Events may, and often do overlap within a schedule. When
events overlap, the Supervisory Controller uses the following
priority structure, from highest to lowest:
1. Maintenance Schedule Event #1
2. Maintenance Schedule Event #2
3. Maintenance Schedule Event #3
4. Events that occur on HD1 (Holiday #1)
5. Events that occur on HD2 (Holiday #2)
6. Events that occur on HD3 (Holiday #3)
7. Events that occur on HD4 (Holiday #4)
8. Maintenance Schedule Events of a slave
schedule’s master schedule (if applicable).
9. Standard events within the schedule itself.
Ranges
In addition to the 15 events within a master or slave schedule,
up to 12 standard ranges may be specified. Ranges are sets
of dates that specify which days within the year the
schedule’s events will be applied. The Site Supervisor checks
the list of ranges to see if the current date falls within any of
the twelve possibilities; if the date does not fall within a range,
none of the schedule’s events will occur.
When no date ranges are specified, the schedule is
considered to be active. All scheduled events will occur
normally.
Holiday Schedules
A Holiday Schedule application’s primary function is to pass
along the day of the week to one or more master or slave
schedules, and to tell these schedules when it is a holiday
(HD1 - HD4). A holiday schedule determines holidays by
cross-referencing the current date with its user-programmed
list of holiday date ranges. During the time periods of these
date ranges, the holiday schedule tells the schedules to
perform the events programmed for one of the four holiday
dates (HD1, HD2, HD3, or HD4).
Because multiple Supervisory Controllers on a network
would likely use the same holiday schedules for
determining special occupied and unoccupied building
hours, holiday scheduling is handled by Global Data. This
means the holiday schedule can be set up in one Supervisory
Controller and shared with all other Supervisory Controllers
that use time scheduling.
9.14.6 Output Calculation
The Time Schedule control algorithm calculates the
current On/Off status, the time until change of state (TUCOS)
and time since change of state (TSCOS) for all the schedules.
This information is available for the other applications that are
making use of a particular schedule. The schedules output
status reflects the results of any bypass or override, but there
is also an output that reflects the actual calculated value
based on the time of day.
The Time Schedule control algorithm runs every minute to
determine the state of the schedule, but a new bypass
request or a new demand shed request is processed
immediately. A termination of a bypass or a demand shed
request is also processed immediately. The Time Scheduling
control algorithm is composed of a core scheduling
algorithm, bypass, override, and demand control handling.
There may be outputs that the Time Schedule does control
directly and in these cases the user is able to enable demand
shedding of the output. If the Demand Control Input indicates
shed and if the schedule output is On, it is turned Off. The
load is turned back On at the next minute advance when the
Demand Control Input indicates restore.
9.14.7 Scheduling Logic
The core scheduling algorithm determines the state of the
active schedule. It does not take bypass, override, and
demand shed inputs into account. The core scheduling
algorithm operates under two different modes: either Master
or Slave as determined by the “Schedule Type” input. The
difference among these two operation modes is the different
usage of some inputs/outputs and their corresponding
values.
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