6
your lifestyle. These loads usually consist of heating or
cooling circuits, dryer heating elements and hot water
heaters. These loads represent 60% to 80% of your total
connected electrical load. With eight or sixteen separate
control points, the 9312 provides maximum utilization
of energy. That’s because the loads which are turned on
and off are smaller, permitting a more regular and even
demand level. This results in greater energy effi ciency and
comfort.
Microcomputer for Maximum
Flexibility
Use of a microcomputer allows the 9312 to precisely
measure KW power demand and accurately compute and
control the average KW demand. In addition, by using a
microcomputer, the 9312 can be adapted to any user life-
style or load requirement by allowing unlimited fl exibility
in choosing load control strategies, Minimum On/Off-
Times and other control system settings.
EEPROM Non-Volatile Memory for
Maximum Reliability
Energy Sentry’s EEPROM memory “remembers”
all system settings, even when power is lost to your unit.
In this way utility power interruptions do not affect the
settings in your 9312. The system’s 10-year non-volatile
memory retains settings for 10 years in absence of power,
and if power is lost, timekeeping continues for 10 years
ensuring that the system clock is always accurate.
Choice of Load Control Strategies
The choice of load control strategies, made possible
by the use of a microcomputer, offers unlimited fl exibility
as to how loads may be controlled. This means the 9312
can be adapted to almost any application, requirement,
or lifestyle. You or your dealer can individually set the
priority of each controlled load to create the optimum load
control strategy for a particular home and lifestyle.
Minimum On/Off-Times to Protect
Heat Pumps and Air Conditioners
Loads
All control points of the 9312 can be programmed
with Minimum On and Off-Times, each variable from
zero to 20 minutes. This feature allows the 9312 to be used
with heat pump and air conditioning compressor loads by
providing time-delay protection.
Auto-Limit Function
The 9312’s Auto-Limit Function allows automatic
changes of the demand limit up to 12 times per year. You
may fi nd this useful in changing their demand limit as
desired throughout the year to refl ect the seasonal increases
or decreases in energy use. The Auto-Limit function helps
to automatically adjust for these changes so you don’t have
to remember to do it manually. You can override these
changes at any time; however, any previously set changes
will still remain in effect.
System Description
Your Energy Sentry 9312 Demand Management
System consists of three basic components: the Control/
Display Unit, Relay Unit(s) and the Current Transform-
ers. The System Diagram in Figure 3 in the Installation
Manual shows how these components are connected to
control loads at the circuit breaker panel. Your 9312 con-
trols only those loads which are connected to it. However
the total demand from all household loads are measured
continuously. These loads will vary depending on applica-
tion and should be listed in the space provided at the end
of this manual; as well as, on the keyboard label inside the
door of the Control/Display Unit. If you are in doubt as
to which loads are controlled, ask your electrician or the
authorized dealer who installed your 9312.
The basic function of your 9312 in controlling these
loads is to keep the total electrical demand below a peak
value set according to your desired level of comfort and
minimum load requirements. Each of the components
which make up the 9312 has a separate and unique func-
tion in accomplishing this task described below:
Control/Display Unit
The Control/Display Unit is located inside the home
usually in a convenient location like the family room,
kitchen, or main hallway. It is used to set or change system
settings and monitor system operation and contains an
audible alarm to indicate that the demand limit is about to
be exceeded. A 6-digit display provides system informa-
tion and the current time. There are 7 push-button keys
that control all functions of the display. By pressing a
key or a combination of keys, you can change the display
mode and program all system settings.
The Control/Display Unit is the “brain” of the 9312
and it contains a microcomputer which automatically
controls loads connected to the relays in the Relay Unit.
Commands to switch these loads originate here and are
based on the user-set demand limit and the actual demand
as measured by the Current Transformers. The loads
are switched based upon the load control strategies pro-
grammed into your unit according to your requirements.
These strategies will be discussed in more detail later.
Relay Unit
Either one or two Relay Units may be used with
the 9312. Each Relay Unit consists of up to eight power
switching relays. This unit is mounted next to the main
circuit breaker panel and contains the Data/Link PC Board
used in communicating with the Control/Display Unit. An
expanded system, one that has 16 power switching relays,
requires two Relay Units.
Current Transformers
Two Current Transformers (CT’s), usually mounted
inside the circuit breaker panel to monitor total electrical
usage. They tell the microcomputer in the Control/Display
Unit how much electricity your home is using for all loads,
not just those controlled by the 9312. By monitoring the
total usage, controlled loads may be turned on and off to
keep total demand below the limit you set.
