STIEBEL ELTRON EAC 5 Instruction Manual

Charge controller
» EAC 5
OPERATION AND INSTALLATION

CONTENTS
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Contents
Scope of delivery ................................... 3
Overview................................................ 4
Functions................................................ 5
Charge Controller .....................................5
Applications ..............................................6
System Control.........................................7
Heat Demand..........................................10
Charge Release......................................14
Charging Models.....................................16
Control System.......................................19
Password System...................................20
User Interface.........................................21
Installation............................................ 22
Mounting.................................................22
Wiring......................................................23
Start-up...................................................26
User menu ........................................... 32
Idle screen..............................................32
Operation................................................35
Information..............................................40
Setup ......................................................42
Installer Menu ...................................... 45
Information ............................................. 50
Service ................................................... 56
Detail Settings ........................................ 56
Appendix.............................................. 69
Sensor characteristics............................ 69
Troubleshooting...................................... 74
Specifications ......................................... 77
Guarantee, environment and recycling 80
Safety and Installation Instructions...... 81
Safety Instructions
When installing this device or working on it always observe
the safety instructions given at the end of this document!

SCOPE OF DELIVERY
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Scope of delivery
Charge Controller EAC 5
Installation quick reference guide EAC 5
(for the installer)
Operation instructions EAC 5
(for the user)
Pencil (Rubber tip can be used to operate the Touch Display)
ENGLISH

OVERVIEW
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Overview
The charge controller EAC 5 has been designed for use in
heating systems with electrical storage heaters.
The EAC 5 implements the basic functions of a central
control unit as defined inthe standard DIN EN 50350:
Calculate the heat demand based on the outdoor tem-
perature,
Process the charge release signals of the distribution
network operator (with/without time function),
Output the charge release signal and the target charge
rate to the storage heaters.
As opposed to a central control unit according to the
standard, the EAC 5 implements additional comfort
functions to meet the preferences of individual users. This
includes e.g. a week program for a timed control of the tar-
get charge rate, a holiday program for vacation periods and
the capability to connect to an internet-based server; see a
subsequent chapter.
The type of outdoor temperature sensor can be chosen from
a range of types well-established in electrical storage heat-
ing systems. For the control signal, a duty cycle AC output
(ED) is provided.
The charge controller EAC 5 provides several applications,
selectable during installation, which allow to choose the
charging model (Classic, Self-learning, Reduced).
Complementary devices
Because of its TGN bus connectivity the charge controller
EAC 5 is compatible to the "Electrical Energy Storage Heat-
ing" family of devices made by tekmar Regelsysteme GmbH.
Additional information about the available devices can be
found at www.tekmar.de.

FUNCTIONS: CHARGE CONTROL
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Functions
Charge Controller
The fundamental difference between the new EAC 5 and a
conventional central control unit is the availability of time
functions.
A central control unit does not know date or time. The reac-
tion on release signals is always spontaneous, i.e. the central
control unit is "surprised" by every new signal and reacts ac-
cording to its parameter settings.
The EAC 5, however, knows the current date and time and
ideally has information on outdoor temperature, release sig-
nals and user preferences (time schedules) for the next 24
hours. This enables the EAC 5 to establish an energy forecast
which calculates and controls the optimal charging within
the next 24 hours.
Accordingly, date and time must always be set correctly in
the EAC 5. If an internet gateway (special accessory from
tekmar) is connected, this will happen automatically through
the internet.
Subsequently, the individual functions of the controller fami-
ly are explained, which can be found in the following menu
items:
Applications
System Control
Heat Demand
Charge Release
Control System
Password System
User Interface
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FUNCTIONS: APPLICATIONS
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Applications
An application which is to be selected during installation de-
fines the charging model:
Classic: Charging model forward or backward control as
per DIN EN 50350 with the familiar parameter settings
Self-learning: Self-learning charging model that can be
used for almost all release models * and adapts the charg-
ing process to the outdoor temperature, the release times
and the user preferences (heat level, time programs) by
means of a forecast calculation
Reduced: like Self-learning, however, for release models
with reduced power demand (e.g. 19 hours charge release
with 55% power reduction) and phase sequence control
(tekmar type PSS)
The selection of an application also includes the definition of
a series of basic settings which can be set individually in the
"Detail settings" menu to match the specifics of a particular
installation.
* not for variable charging models, where the release times depend
on outdoor temperature or dayof week. For these, the correct se-
lection is Classic / Forward control w/o time function .

FUNCTIONS: SYSTEM CONTROL
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System Control
The system control summarizes the results of the heat de-
mand calculation and the charge release, forwards these to
the selected charging model and applies
preferences in order to calculate the charging and finally to
output the charging signals as per selected output model.
By setting the operating mode, the heat level and the weekly
or holiday program, the user can define the target room
temperature which the system is to achieve, depending on
the time of day and day of week. Additional parameters al-
low to scale the heat level. The heat level 3.0 always refers to
the heat limit temperature set by E2 in the heating curve
plus 2 K internal gain of the room (factory default 18 °C + 2 K
= 20 °C).
Selectable operating modes:
Standby: heating operation off, only frost protection ac-
tive
Manual: manual setting of the heat level through the
menu or online
Automatic: time-dependant automatic setting of the heat
level through weekly programs and holiday periods
Heat level adjustment:
Frost protection: room temperature reduction to the pre-
set frost protection level (factory default 10 °C)
1.0 ..:minimum target room temperature
(factory default 15 °C)
.. 5.0: maximum target room temperature
(factory default 25 °C)
Charging model
The control model defines how the target charge rate is cal-
culated from the desired heat level, the heat demand and
the charge release. The available charging models depend
on the application Classic or Self-learning (or Reduced).
Classic charging models as per DIN EN 50350:
Forward control without time function (FWCw/oT)
Forward control with time function (FWCwT)
Backward control (BWC)
For a description of these charging models see the corre-
sponding standard.
Self-learning charging models of the EAC 5:
Temperature forecast (TempFcast)
Energy forecast (EnerFcast)
The energy forecast summarizes the future trends of heat
demand, release values and user preferences and calculates
the resulting target charge rates of the next 24 hours by
means of a simulation of the flat.
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FUNCTIONS: SYSTEM CONTROL
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The temperature forecast is an automatic fallback system in
case the input data for the energy forecast is not entirely
present as a time series. To calculate the target charge rate
only the current data at the point in time "now" is taken into
account.
The following table shows for which release method (see
section Charge Release, page 14) the individual charging
models can be used (Bold print = optimal setting).
Charging
model
Release
method
Forward without
time function
Forward with
time function
Backward
Energy
forecast
Variable
LF/LZsignals
yes
no
no
no
Fixed
LF/LZ signals
yes
yes
yes
yes
Output model
The output of the signals to the main contactor (output SH)
and to the storage heaters is adjusted to the operating mode
of the installation by means of the control model for the SH
contactor:
SH Release: the SH output is switched on when the charge
release signal is present (on delay 25 s), and the ED signal
takes safety steps if the target charge rate = 0 orif the
charge release is missing (signal values as per DIN EN
50350that represent a negative rate of charge).
SH Charging: like SH Release, however, the SH output is
switched on only if the target rate of charge > 0.
CR Standby: the SH output is switched on or off depend-
ing on the release signal; the target charge rate is continu-
ously output through the ED signal, independent of the re-
lease signal (only for special cases).
ED Switch-off: the SH output works as with SH Charging
(on delay 480 s), however, the ED signal is switched off if
the target charge rate is =0 or if the charge release is miss-
ing.
The model ED Switch-off should particularly be used for
storage heaters with thermo-mechanic charge controllers.
Switching off the ED control voltage outside the release pe-
riods saves the energy for heating these controllers, particu-
larly during summertime. If electronic controllers are present
this model cannot be used as these can possibly recognize
this as a fault and switch to emergency operation.
The control of the signal output can assume the following
states:

FUNCTIONS: SYSTEM CONTROL
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Reset: initialising
Switched Off:signal output switched off;
charge signal = 0%, SH relay off
Start-up:starting upfor 120 s after controller power-up;
charge signal = 0%, SH relay off
Off Standard: no release signal, or where appropriate tar-
get charge rate = 0%;
charge signal = 0%, SH relay off
Off ED Thermic: no release signal, or target charge rate =
0%;
charge signal ED switched off, other charge signals =0%,
SH relay off
Off SH Standby: no release signal;
charge signal according to calculation, SH relay off
Starting: signal output is starting as release signal is pre-
sent and target charge rate > 0%, delay time running;
charge signal according to calculation, SH relay off
Operation: normal operation, release signal present and
where appropriate target charge rate > 0%;
charge signal according to calculation, SH relay on
Note: When using the models CR Standby or ED Switch-off it
is essential to switch the heating current of the entire instal-
lation with a main contactor which is driven from the SH
output.
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FUNCTIONS: HEAT DEMAND
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Heat Demand
Depending on availability, the heat demand calculation is
based on the outdoor temperature values measured by the
temperature sensor which is connected to the system (by
wire, alternatively by radio) or optionally with additional
tekmar devices. Both sources are evaluated independently of
each other as individual values or, if possible, as a time series.
If both sources are equally available the weather forecast
takes precedence for the determination of the effective out-
door temperature as it provides a more substantiated future
prediction.
Additionally, the system carries along an outdoor tempera-
ture substitute value which is automatically adjusted to the
current effective outdoor temperature on a daily basis and
can be adjusted manually if failures persist over extended
periods.
The result of the heat demand calculation is the current heat
demand and as far as can be determined the future series
of the heat demand for the next 24 hours.
States
Depending on the availability of both of these sources, the
heat demand calculation can assume the following states:
Reset: initialising
Substitute value: both sources at fault, substitute value is
used
OT Measured value: outdoor temperature sensor active,
only measured value available (normally for some time af-
ter power-up)
OT Value now:outdoor temperature sensor active, current
individual value including building thermal inertia availa-
ble
OT Value trend: outdoor temperature sensor active, time
series with pseudo future available
Weather hour: weather forecast active, only single value
for the next hour available
Weather future: weather forecast active, only forecast
available
Weather now:weather forecast active, current single val-
ue including building thermal inertia available
Weather trend: weather forecast active, complete time se-
ries available
Error: calculation module internal error
Building thermal inertia
The indoor temperature of a building follows a change of the
outdoor temperature only with a time delay that depends
mainly on the building mass (type of structure) and its insu-
lation. An efficient heat demand calculation must take this

FUNCTIONS: HEAT DEMAND
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into account as otherwise unnecessary heating phases
would occur, particularly during the transitional period.
To match this calculation with the respective building the
two main influencing factors can be set through a single pa-
rameter.
Type of
structure
Insulation
light
normal
heavy
bad
light +
bad
normal +
bad
heavy +
bad
normal
light +
normal
normal +
normal
heavy +
normal
good
light +
good
normal +
good
heavy +
good
For testing purposes the building thermal inertia can be dis-
abled.
The past values of the outdoor temperature (outdoor tem-
perature sensor or historical weather data) are subject to the
selected delay time and result in the so-called "effective out-
door temperature".
Heating characteristic
The heating characteristic is defined by three parameters
and uses the effective outdoor temperature to calculate the
heat demand and thus the target charge rate, which is
passed on to the storage heaters and the charging control-
lers, respectively.
Full charging (E1): rated outdoor temperature which re-
quires the heating system to provide its full power to
achieve the standard room temperature of 20 °C (heat
demand = 100%)
Start of charging (E2): outdoor temperature below which
the heating operation commences
Base charge at start of charging (E15): target rate of
charge to be output at start of charging
The E numbers refer to the definitions given in the standard
DIN EN 50350.
Thus, the heat demand is varied through the heating charac-
teristic from the base charge at start of charging to 100% at
rated full power.
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FUNCTIONS: HEAT DEMAND
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Here, the rated outdoor temperature is a fixed value of the
heating installation inside the building. Initially, the base
charge depends on the type of heating element, however, it
can be modified to some extent by the user preferences. The
start of heating can be adjusted to the individual user pref-
erences.
Heat demand factor
Frequently, houses and flats that are equipped with electrical
storage heating are already older and have been energetical-
ly improved since their construction (e.g. by fitting new win-
dows or a cladding insulation) without the heating installa-
tion having been adapted accordingly. In these cases, the
parameter heat demand factor allows to match the current
heat demand at design temperature with the original heat
demand at system installation time.
The heat demand factor corrects the heat demand calculat-
ed from the heating characteristic to the new value required
after refurbishment.
The new heat demand has to be calculated (heat require-
ment calculation) or estimated. An estimation can be based
on e.g. a typical specific heating load which is assumed for
the year of construction or the year that corresponds to the
refurbishment standard, respectively:

FUNCTIONS: HEAT DEMAND
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Year of construction
Heating load [W/m²]
< 1958
180
1959-68
170
1969-73
150
1974-77
115
1978-83
95
1984-94
75
> 1995
60
KFW 60
50
KFW 40
40
Passive house
15
The heat demand factor is calculated as:
HDF = Heating load(Refurbishment) / Heating load(Year of
construction) * 100
Example: Year of construction 1966 and Year of refurbish-
ment standard 1990 makes a HDF of 75/170*100 = 44%.
A heat demand factor (HDF) calculated by this method
should be adapted according to the user experience some
time after installation of the controller (too cold: increase
HDF, too warm: decrease HDF).
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FUNCTIONS: CHARGE RELEASE
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Charge Release
The charge release is derived from the release information of
the distribution network operator (DNO) and determines
when a charging of the storage heaters may occur.
This is done by the charge controller and is based on the sig-
nals LF, LZ and LL as defined in the standard EN 50350 which
are normally created locally by a ripple control receiver or a
time switch.
These release signals have the following functions:
LF: standard charge release for the main charging period
(in classic charging models the 8 hours charging at night)
or the additional charging time with low tariff.
LZ: additional charge release, e.g. for additional charging
during the afternoon; possibly with high tariff if required,
signal is not used by every DNO.
LL: start signal of clockwork that starts the time functions
of the charging models backward control (BWC) and for-
ward control with time (FWCwT); signal is sent separately
only by a few DNOs.
Concerning the use of these signals the technical connection
conditions of the corresponding network operator have to
be followed in any case.
Release memory
To have a future series of release times available for self-
learning charging models, this application stores the release
signals of the past 24 hours in steps of 15 minutes as it is to
be expected that the release times of the next 24 hours will
repeat in the same way.
Note: This does not or only conditionally apply to release
signals that depend on outdoor temperatures or week days
and holidays; thus this function is not suitable for such re-
lease signals of the DNO. Normally, these cases only allow
the use of the classic charging model forward control w/o
time (FWCw/oT). Alternatively, one can apply to the network
operator and ask for fixed release times.
Linkage LF-LL
As nearly all DNOs supply the signals LF and LL simultane-
ously (if LL is transmitted at all), the controller provides an in-
ternal linkage function that uses the LF input to create not
only the LF signal but also the LL signal. This linkage can be
disabled by a parameter and assigned to the input LX to feed
the controller with a separate LL signal. For the self-learning
charging models LL is not required.

FUNCTIONS: CHARGE RELEASE
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High tariff charging lock
Frequently, electrical storage heating systems are sized such
that an additional charging time during the day, if available,
is needed only in cold weather. If this additional charge is
billed at high tariff it is even more desirable to use the addi-
tional charging time only on particularly cold days.
To achieve this a high tariff inhibit signal can be defined that
refers to the input LZ or LX (if not assigned to a separate LL
signal, see above), respectively, and the parameter of which
offers the following selections:
Off: no high tariff lock
LZ HT: high tariff lock if LZ = on
LX HT: high tariff lock if LX = on
LX NT:high tariff lock if LX = off
The corresponding temperature limit, above which the lock
is effective, can be set or disabled in the heat demand sec-
tion.
Time function cut-off
When using the charging models FWCwT or BWC the time
function can be temporarily disabled (the clockwork keeps
running independent of this cut-off) by simultaneously excit-
ing the terminals LF and LZ and activating the model
FWCw/oT. Depending on the value of the parameter FBD
this is effective either only during the night or during the en-
tire day.
States
Accordingly, for charge release the following states are de-
fined:
Reset: Initialisation
Off: processing release off
L* signals: release is based on signal inputs LF and LZ.
Memory learning: like L* signals, release memory activat-
ed but still in learning mode (for up to 24 hours after pow-
ering-up the controller).
Memory: like L* signals, additionally calculated charge re-
lease prediction for the next 24 hours available.
The result of the charge release calculation is the current
charge release and as far as can be determined the future
series of the charge release for the next24 hours.
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FUNCTIONS: CHARGING MODELS
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Charging Models
A charging model translates the identified heat demand, the
settings into a target charge rate. Depending on the selected
application, one or more of the following charging models
are available.
Energy forecast
For the energy forecast, the future values of the heat de-
mand, the release signal and, if required, control values of
the distribution network operator are used, together with
the heat level desired by the user, to determine the current
and the future charging demands by means of a simulation
of the next 24 hours. Additional to these time series, the pa-
rameters installation type and charging time for 100%
charge are evaluated.
The timed heat level presets are to be defined by a week
program which makes sure that the charging is adjusted ac-
cording to the comfort requirements of the user (e.g. as a
night-time set-back). With this charging model, a manually
adjusted heat level is normally not reasonable.
The energy forecast requires a predictive release for the sim-
ulation and thus is reasonably usable only with the release
methods fixed LF/LZ signals, release program and timetable.
Note: The model energy forecast should not be used in con-
junction with charging times that depend on the outdoor
temperature as this can occasionally lead to unsuitable
charge predictions.
The system states of this model are:
EnerFcast Off: charging model not activated (no release or
no heat demand)
EnerFcast RTtarg: calculation of target charge rate with
heat demand correction by target room temperature.
Temperature forecast
The temperature forecast model is the automatic fall-back
model in case there is no sufficient time series for an energy
forecast.
The required charging is determined by the current release,
the current value of the effective outdoor temperature and
as far as available the time series of an outdoor tempera-
ture forecast. The corresponding heat demand is calculated
from the heating characteristic; corrected, if need be, by a
deviating target room temperature or a control value of a
timetable.
The system states of this model are:
TempFcast Off: charging model not activated (no release
or no heat demand)

FUNCTIONS: CHARGING MODELS
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TempFcast RTtarg: calculation of target charge rate with
heat demand correction by target room temperature.
Classic as per DIN EN 50350
The charging models forward control (FWC) and backward
control (BWC) are the classic charging models according to
DIN EN 50350. This standard and the charging methods de-
fined therein were developed when analogue electronic
controllers with mechanical clockwork were still state of the
art. Accordingly, their "intelligence" is limited to counting
the time and directly processing the effective outdoor tem-
perature.
The two forward control models FWC differ in the way the
time information is treated by the clockwork release (logic
signal LL, normally combined with LF). The model FWCw/oT
ignores the time information, i.e. with every release the
charging is based on the target charge rate from the heating
characteristic and the current heat level. In the model
FWCwT, the charge rate drops down to the corresponding
additional daytime charge (E10) after the daytime changeo-
ver (E12).
These methods are mainly used with charging times 8+0h
and 8+2h, respectively. Other charging times can be imple-
mented, this, however, frequently requires a precise adjust-
ment of the time parameters E3, E11, E12, E13 as well as, if
required, E14 and/or a separate processing of the clockwork
release LL (see section Charge Release, page 14).
The following sketch shows a typical trend of a target charge
rate over a day in a backward control including the E para-
meters involved:
ENGLISH

FUNCTIONS: CHARGING MODELS
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In the control models FWCwT and BWC the correct determi-
nation of the runtime, i.e. the reading of the electronically
emulated historical clockwork, is essential. The clockwork is
started with the signal LL at the beginning of the night
charging time and stopped after the lapse of E13 until a new
start occurs.
In case of a loss of power the controller restores the reading
of the clockwork, precisely timed, from the last start of LL
and the current time of day. Should the controller have lost
its time due to an extended loss of power (e.g. summer
switch-off), it is possible to set the current runtime manually
additional to the time of day.
Due to their fixed structures and their use in conjunction
with the traditional "night charging times" these models are
not (BWC) or hardly (VWC) usable in conjunction with week
programs that work with varying heat levels over the day.
The parameters E1 (full charging), E2 (start of charging) and
E15 (base charge at start of charging), additionally specified
in the standard, define the heating characteristic of the in-
stallation and are valid for all charging models. Hence, they
are contained in the heat demand section.
States
The system states of these models are:
Off: Charging model not activated (fault)
Night operation: runtime E12, LF not set
Night release: runtime E12, LF set, no charging
Night charging: runtime E12, LF set, charging active
Day operation: runtime E12, LF/LZ not set
Day release: runtime E12, LF/LZ set, no charging
Day charging: runtime E12, LF/LZ set, charging active
End of day: runtime E13, re-start with activation LL
Forward w/o time: charging as per heating characteristic
without runtime
Fault LF mon: fault detected by LF monitoring (only floor
heating installations)
For additional explanations of these charging models see
DIN EN 50350.
Note: The models FWCwT and BWC must not be used in con-
junction with outdoor temperature dependent charging
times.

FUNCTIONS: CONTROL SYSTEM
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Control System
The control system outputs the target charge rate to the
storage heater devices.
The AC control system, due to its nature as a burst-firing con-
trol also called ED system (Einschalt-Dauer = duty cycle),
works with a control signal in the 230 V power line.
The ED system can be set to different specific values (e.g.
80%, 72%, 37%), with the specific value defining the duty cy-
cle of the burst-firing control which represents a target
charge rate of 0%. Thus, if ED system = 80% a duty cycle of
80% transmits a target charge rate of 0%. (Attention, reverse
relationship: high ED value = low charge rate)
With the ED system it is necessary to differentiate between
electronic and thermo-mechanical controllers in the storage
heaters. Thermo-mechanical controllers require a compensa-
tion of the line voltage (power measurement) which would
lead to false readings of the charge rate in electronic control-
lers (counting of the 50 Hz half waves). Electronic controllers,
however, frequently have a control signal loss detection. For
these controllers, an ED signal representing 100% target
charge rate still must have a base duty cycle of 2%.
All characteristics of the control signals are adjustable
through corresponding parameters.
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FUNCTIONS: PASSWORD SYSTEM
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Password System
The controllers provide a facility to set passwords for four
menu levels (level 0 Information is always freely accessible).
This e.g. makes sense to ensure that the controller can be
configured only by qualified personnel. A password consists
of four digits and can be set individually for each of the four
levels. The password 0000 disables the password protection
of the corresponding level.
Password protection of the menu items:
Information
Level 0
Operation
Password level 1
Setup
Password level 2
Installer
Password level 3
A password for a higher level is also valid for the levels be-
low, i.e. somebody who has access to a higher level, has au-
tomatically access to the levels below even if the passwords
of these levels are not known.
In case a password is forgotten or is not accessible any more
for another reason (e.g. change of the installer) a super
password allows to delete the passwords of the levels 1 to 3
and thus to unlock the controller. The super password is
documented in the chapter "Installation". In case of prob-
lems the technical customer service can be contacted.
Note: The password of a lower level can be set only if all
passwords of the higher levels have already been set.
Factory settings:
0000 for levels 1, 2 and 3.