Emerson E2 Manuel D’Utilisation

Each schedule may also be given up to three pairs of 

temporary schedule events. These events start and end at 
specific days and times and do not continue past those 
dates (in other words, temporary events cannot be made to 
occur weekly or annually).

Events may, and often do overlap within a schedule. 

When events overlap, the E2 uses the following priority 
structure, from highest to lowest:

1. Temporary Schedule Event #1

2. Temporary Schedule Event #2

3. Temporary 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. Temporary Schedule Events of a slave schedule’s 

master schedule (if applicable).

9. Standard events within the schedule itself.

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 E2 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 con-

sidered to be active. All scheduled events will occur nor-
mally.

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 hol-
idays 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 E2s on a network would likely use 

the same holiday schedules for determining special occu-
pied and unoccupied building hours, holiday scheduling is 
handled by Global Data. This means the holiday schedule 
can be set up in one E2 and shared with all other E2s that 
use time scheduling.

A Power Monitoring application is used primarily for 

monitoring, recording, and to a lesser degree controlling 
KW usage in a building.

Power companies supply power to consumers at a 

fixed rate per kilowatt hour until a pre-defined level of 
energy consumption is reached. This level is called the 
demand limit. When the demand limit is exceeded, the 
rate is greatly increased as a penalty for high power 
demand by the consumer. Generally, once the demand 
limit is exceeded, the increased rate is charged for the 
remainder of the year.

To determine if you have reached the demand limit, the 

power company arbitrarily monitors a consumer’s energy 
consumption for a fixed period of time. This monitoring 
period is called a demand window. Power companies can 
generally tell you how long a demand window period 
lasts, but you’ll never know when the measurement will 
take place.
How Power Monitoring Calculates Demand

To help you make sure you do not use more power than 

the demand limit, the E2’s Power Monitoring applications 
determine your current KW usage in much the same way 
as your power company. Power Monitoring uses a watt-
hour transducer input to determine the current KW usage. 
Multiple KW values are averaged together into “demand 
windows,” much like the ones power companies use. 

Then, depending on how the application is configured, 

the most current KW value is compared to a demand set-
point. The “current KW value” in this case may be either 
the instantaneous value read by the power transducer, or it 
may be the average of all KW transducer readings taken 
over 1-minute intervals. This setpoint should be equal to 
or slightly lower than the demand limit set by your power 
company.

In short, since E2 doesn’t know when the power com-

pany’s demand window will begin, the E2 measures power 
as if the demand window could happen at any time. This 
way, E2 can more accurately determine when your site is 
approaching or exceeding the demand limit.
Shed Mode

If the KW usage is higher than the demand setpoint, 

Power Monitoring goes into Shed Mode. During Shed 
Mode, Power Monitoring turns on a digital output called 
SHED OUT. This output may be connected to the demand 
shed inputs of one or more E2 applications, which will in 
turn shut down or otherwise curb the power usage of the