Caleffi solar iSolar Plus 24V User manual

ISOLAR PLUS 24V
Mounting
Connection
Operation
Fault diagnostics
Application examples
Thanks for buying this product.
Read this manual carefully to get the best perfomance from this unit. manual
49006580
*49006580*

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Contents
Safety advice........................................................................2
Technical data and overview of functions ........................3
1. Installation .............................................................4
1.1 Mounting.................................................................................. 4
1.2 Electrical Connection ........................................................... 4
1.2.1 Data communication / Bus............................................. 5
1.2.2 Standard solar system........................................................... 5
1.2.3 Solar system and heat exchange ........................................ 6
1.2.4 Solar system and afterheating............................................. 6
1.2.5 Solar system and tank charge in layers............................. 7
1.2.6 2-tank-solar system valve logic........................................... 7
1.2.7 2-tank-Solar system pump logic ......................................... 8
1.2.8 Solar system with 2 collectors ........................................... 8
1.2.9 Solar system afterheating by solid fuel boiler.................. 9
1.2.10 Solar system with heating circuit return flow incr.......... 9
2. Opearation and function ....................................10
2.1 Adjustment buttons ............................................................10
2.2 System monitoring display ................................................. 10
2.2.1 Channel indication............................................................... 10
2.2.2 Tool bar.................................................................................. 10
2.2.3 System screen.......................................................................11
2.3 Blinking codes....................................................................... 11
2.3.1 System-Screen Blinking codes........................................... 11
2.3.2 LED blinking codes..............................................................11
3. Primary commissioning......................................12
4. Control parameter and display channels..........13
4.1 Channel overview................................................................ 13
4.1.1-6 Indication channels ..............................................................15
4.1.6-21 Adjustment channels........................................................... 16
5. Tips for fault localization....................................21
5.1 Various .................................................22
6. Accessory .............................................................24
Safety advice
Please pay attention to the following safety advice in order
to avoid danger and damage to people and property.
Instructions:
Attention should be paid to
- valid local regulations
- the statutory provisions for prevention of industrial acci-
dents,
- the statutory provisions for environmental protection,
- the Health and Safety at Work Act 1974
- Part P of the Building Regulations 2005
- BS7671 Requirements for electrical installations and rele-
vant safety regulations of DIN, EN, DVGW,TRGI,TRF and
VDE.
These instructions are exclusively addressed to authorised
skilled personnel.
- Only qualified electricians should carry out installation and
maintenance work.
- Initial installation should be carried out by named qualified
personnel
Declaration of conformity
The product complies with the relevant direc-
tives and is therefore labelled with the CE mark.
The Declaration of Conformity is available upon
request, please contact the manufacturer.
Subject to change without prior notice. Errors excepted

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!



• System-monitoring-display
• Upto4temperaturesensors
Pt1000
• 9basicsystemsselectable
• Heatbalancing
• VBus®
• Functioncontrol
• Thermostatfunction
(time controlled)
• Parameterisationandcontrol
of the system by ServiceCenter;
Software is possible
• User-friendlyoperationbysimple
handling
• Housinginoutstandingdesign
and compact dimensions, easy to
install
Technical data
Housing:
plastic, PC-ABS and PMMA
Protection type: IP 20 / DIN 40050
Ambient temp.: 32 ... 104 °F
Size: 172 x 110 x 46 mm
Mounting: wall mounting, mounting
into patch-panels is possible
Display: System screen for system
visualisation,16-segment display,7-seg-
ment display, 8 symbols for system
status and operating control lamp
Operation: by 3 pushbuttons in the
front of the housing
Functions: Differential temperature
controller with optional add-on system
functions. Function control according
to BAW-standards, operating hours
counter for solar pump,tube collector
special function, thermostat function
and heat quantity balancing.
Inputs:
for 4 temperature sensors Pt1000
Outputs: 2 electromechanical relays
Bus:VBus®
Power supply:
24V
Total power supply:
2 (1) A 24 V
Scope of delivery:
1 x iSolar Plus 24V
1 x accessory bag
1 x spare fuse T4A
2 x screws and dowels
4 x strain relief and screws
Additionally enclosed in the full kit:
2 x sensor FKP6
2 x sensor FRP6

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VBus®
display
pushbutton
can fuse 4A
cable conduits with strain
relief
cover
12
S1 S2 S3
3456
Temp. Sensor
Pt1000
R1R2
201918171615
S4
78 141312
VBus
910
1 (1) A
1
24 V
(1) A 24 V
R1
R2
T4A
24 V
CALEFFI
NORTH AMERICA, Inc.
Milwaukee,WI 53208
1.1 Mounting
This unit must only be located internally. It is not suitable
for installation in hazardous locations and should not be
sited near to any electromagnetic field.The controller must
additionally be equipped with an all-polar gap of at least 3 mm
or with a gap according to the valid installaton regulations,
e.g. LS-switches or fuses. Please ensure sensor cables and
ac power supply are separated
1. Unscrew the cross-head screw of the cover and remove
it from the housing.
2. Mark the upper fastening point on the subsurface
and premount the enclosed dowel and screw.
3. Mount the housing to the upper fastening point and mark
the lower fastening point on the subsurface (pitch of hole
130 mm), afterwards set the lower dowel.
4. Mount the housing to the top and fix it with the lower.
fastening screw.
.
1. Installation Warning!
Switch-offpowersupplybefore
opening the housing.
1.2 Electrical connection The power supply to the controller must only be made by
an external power supply switch (last step of installation!)
and the line voltage must be 24 Volt. Flexible lines are to
be fixed at the housing by enclosed strain relief supports
and screws.
The controller is equipped with 2 standard relays, to which
the consumers e.g. pumps, valves etc. can be connected:
• Relay 1
18 = conductor R1
17 = neutral conductor N
13 = ground clamp
• Relay 2
16 = conductor R2
15 = neutral conductor N
14 = ground clamp
The temperature sensors (S1 up to S4) will be
connected to the following terminals independently of the
polarity:
1 / 2 = Sensor 1 (e.g. Sensor collector 1)
3 / 4 = Sensor 2 (e.g. Sensor tank 1)
5 / 6 = Sensor 3 (e.g. Sensor collector 2)
7 / 8 = Sensor 4 (e.g. Sensor tank 2)
The power supply is effected to the clamps:
19 = neutral conductor N
20 = conductor L
12 = ground clamp
net clamps
fuse
consumer clampsSensor clamp
fastening
fixing
ground clamp
Electrostatic discharge can lead to damages of elec-
tronic components!
Dangerous voltage on contact!

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S1
S2
S4 / TRF
1.2.2 Allocation of clamps for system 1 Standard solar system with 1 tank,1 pump and 3 sensors.
Sensor S4 / TRF can optionally be used for heat quantity
balancing.
R1
Arr 1
S3
1.2.1 Datacommunication/Bus The controller comes with aVBus®for data communication
and energy supply of external modules.The connection
is effected with optional polarity at the clamps marked
with„VBus®“.Via this data Bus you can install one or more
VBus®modules, e.g.:
• heat quant. measurement module WMZ
• large display GA3
• Data logger, DL1
• Data teleindication, DFA2
Additionaly, the controller can be connected to the PC with
the help of a RS-COM adapter. With the ServiceCenter
Software (RCS) the controller parameters can be changed,
measurements can be read out, processed and visualised.
The software enables an easy function control and adjust-
ment of the system.
1 2
S1 S2 S3
3456
Temp. Sensor
Pt1000
R1R2
201918171615
S4
7 8 141312
VBus
910
1 (1) A
1
24 V
(1) A 24 V
R1
R2
T4A
24 V
CALEFFI
NORTH AMERICA, Inc.
Milwaukee,WI 53208
VBus
connection clamps
Symbol Specification
S1 Collector sensor
S2 Tank sensor below
S3 Tank sensor at the top
(optionally)
S4 / TRF Sensor for heat quantity
measurement (optionally)
R1 Solar pump

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R2
S1
S2
R1 S3
S4 / TRF
1.2.4 Allocation of clamps for system 3 Solarsystemandafter-heatingwith 1 tank, 3 sensors
and after-heating. Sensor S4 /TRF can optionally be used for
heat quantity balancing.
Arr 3
S1
S3
S4
R1
R2
S2
1.2.3 Allocation of clamps for system 2 Solar system and heat exchange with an existing
tank with 1 tank, 4 sensors and 2 pumps.
Arr 2
Tank 1
Tank 2
Symbol Specification
S1 Collector sensor
S2 Tank sensor lower
S3 Tank sensor at the top
S4 Tank Sensor 2
R1 Solar pump
R2 Pump for heat exchange
Symbol Specification
S1 Collector sensor
S2 Tank sensor lower
S3 Tank sensor at the top
S4 / TRF Sensor for heat quantity
balancing (optional)
R1 Solar pump
R2 Pump for heat exchange

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1.2.5 Allocation of clamps for system 4
1.2.6 Allocation of clamps for system 5
S2
R1
S3
R2
S1
Solar system and tank charge in layers with 1 tank,
3 sensors, 1 solar pump and 3-way-valve for tank charge
in layers. Sensor S4 / TRF can optionally be used for heat
quantity balancing.
2-tank-solarsystemwithvalvelogic with 2 tanks,
3 sensors, 1 solar pump and 1 3-way-valve. Sensor S4 / TRF
can optionally be used for heat quantity balancing.
R2
S4 / TRF
S1
R1
S2 S3
S4 / TRF
Arr 4
Arr 5
Tank 1 Tank 2
Symbol Specification
S1 Collector sensor
S2 Tank sensor lower
S3 Tank sensor at the top
S4 / TRF Sensor for heat quantity
balancing (optionally)
R1 Solar pump
R2 3-way-valve
Symbol Specification
S1 Collector sensor
S2 Tank sensor 1
S3 Tank sensor 2
S4 / TRF Sensor for heat quantity
balancing (optionally)
R1 Solar pump
R2 3-way-valve

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1.2.7Allocation of clamps for system 7 Solarsystemwitheast-westcollectors, 1 tank,
3 sensors and 2 solar pumps.
R1 R2
S1
S2
S3
Arr 7
S1
S2 S3
R1 R2
1.2.6 Allocation of clamps for system 6 2-tank-solarsystemwithpumplogic with 2 tanks, 3
sensors and 2 solar pumps.
Arr 6
Tank 1 Tank 2
S4
Symbol Specification
S1 Collector sensor
S2 Tank sensor 1
S3 Tank sensor 2
S4 Measuring sensor
(optinal)
R1 Solar pump 1
R2 Solar pump 2
Symbol Specification
S1 Collector sensor
S2 Tank sensor 1
S3 Collector sensor 2
S4 Measuring sensor
(optinal)
R1 Solar pump collector 1
R2 Solar pump collector 2

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S1
S3
S2
S4
R2
R1
S1
S4
S2
S3
R1
R2
1.2.8 Allocation of clamps for system 8
1.2.9 Allocationofclampsforsystem9
Solarsystemwithafter-heatingbysolidfuelboiler
with 1 tank, 4 sensors, 1 solar pump and 1 pump for after-
heating.
Solar system and heating circuit reverse raising with
1 tank, 4 sensors, 1 solar pump and 1 3-way-valve for heating
circuit reverse raising.
Arr 8
Arr 9
Symbol Specification
S1 Collector sensor
S2 Lower tank sensor
S3 Upper tank sensor
S4 Tank for solid fuel boiler
R1 Solar pump
R2 Pump for solid hot
fuel boiler
Symbol Specification
S1 Collector sensor
S2 Lower tank sensor
S3 Upper tank sensor
S4 Heating circuit return
R1 Solar pump
R2 3-way-valve

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1
3
2
backward forward
SET
(selection / adjustment mode)
The system monitoring display consists of 3 blocks: indica-
tion of the channel, tool bar and system screen (active
system scheme).
The indication channel consists of two lines.The upper
line is an alphanumeric 16-segment indication in which mainly
the channel names / menu items are shown. In the lower
7-segment indication,the channel values and the adjustment
parameters are indicated.
Temperatures and temperature differences are indicated in
°F / °C or Ra / K.
2.2.1 Channel indication
indication channel only
2.2.2 Tool bar
The additional symbols of the tool bar indicate the current
system status.
tool bar only
2. Opeartion and function
2.1 Pushbuttons for adjustment
The controller is operated by 3 pushbuttons below the
display. The forward-key (1) is used for scrolling forward
through the indication menu or to increase the adjustment
values. The backwards-key (2) is accordingly used for the
reverse function.
For adjustment of last indication channel, keep button 1
pressed for 3 seconds.If an adjustment value is shown on
the display, SET is indicated. In this case you can press the
key „Set“ (3) in order to change into input mode.
Select a channel by keys 1 and 2
Shortly press key 3, so that SET is blinking.
Adjust the value by keys 1 and 2
Shortly press key 3, so that SET permanently appears,
the adjusted value is now saved.
2.2 System monitoring display
!



Full Monitoring-Display
Symbol standard blinking
relay 1 active
relay 2 active
maximum tank limitation
active / maximum tank
temperature exceeded
collector cooling function or
reccoling function active
antifreeze- function activated collector minimum limitation
or antifreeze function active
collector security shutdown or
tank securtiy shutdown active
+ sensor defect
+ manual operation active
an adjustment channel is
changed SET-mode

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The system screen (active system scheme) shows the
schemes selected on the controller. It consists of several
system component symbols, which are - depending on the
current status of the system - either flashing, permanently
shown or hidden.
Sensors
Collector 1
Collector 2
Pumps
Heating circuit
Sensor
Additional symbol for
operation of the burner
Valve
Tank
Tank heat-exchanger Tank 2 or afterheating (with
an additional symbol)
upper sensor tank
Valve
Pump
3-way-valve
The flow direction or the
current breaking capacity
is always shown.
Heatingcircuit
Tanks 1 and 2
with heat-exchanger
Afterheating
with burner symbol
Temperature sensor
2.2.3 System screen
System Screen only
Constantly green: everything all right
Red/green blinking: initialisation phase
manual operation
Red blinking: sensor defect
(sensor symbol is quickly blinking)
2.3 Blinkingcodes
2.3.2 LED blinking codes
2.3.1 System screen blinking codes
•Pumps are blinking during starting phase
•Sensors are blinking if the respective sensor-indication
channel is selected.
•Sensors are quickly blinking in case of sensor defect.
•Burner symbol is blinking if after-heating is activated
Collectors
with collector sensor

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3. Primary commissioning
For primary commissioning the system scheme has to be adjusted first
1.AC power supply must be activated at first.The controller
passes an initialisation phase during which the operating
control lamp is blinking red and green.After having finished
the initialisation, the controller is in automatic operation
with factory settings. The preadjusted system scheme is
Arr 1.
2. Clock time adjustment in channel TIME. By pressing the
button once you can adjust hours, pressing it
once again the minutes.The time can be adjusted by buttons
1 and 2 and saved by pressing the button.
3. - select adjustment channel Arr
- change into -mode (see 2.1)
- adjustment are saved by pressing button
Now the controller is ready for operation and should enable
an optimum operation of the solar system with the factory
settings.
System survey:
Arr 1 : standard solar system
Arr 2 : solar system with heat exchange
Arr 3 : solar system with after-heating
Arr 4 : solar system with tank charge in layers
Arr 5 : 2-tank solar system with valve logic
Arr 6 : 2-tank solar system with pump logic
Arr 7 : solar system with 2 collectors and 1 tank
Arr 8 : solar system with after-heating by solid hot fuel
boilers
Arr 9 : solar system with heating circuit reverse raising
1
3
2
backward forward
SET
(selection / adjustment mode)
operating control lamp
Arr 1 Arr 2
Arr 3 Arr 4
Arr 5 Arr 6
Arr 7 Arr 8
Arr 9

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4. Control parameter and indication channels
4.1 Channel-overview
Legend:
x
Corresponding channel is available.
x*
Corresponding channel is available if the appropriate option
is activated.

Corresponding channel is only available if the option heat
quantity measurement is activated (OHQM).
MEDT
The channel antifreeze content (MED%) is only shown
if theantifreezeisnotwaterorTyfocorLS/G-LS
(MEDT 0 or 3). Adjustments concerning the antifreeze
content will only make sense if the antifreeze is used in the
solar circuit.

Corresponding channel is only available if the option heat
quantity measurement is deactivated (OHQM).
Please note:
S3 and S4 are only indicated in case of sensors connected
Channnel Arr Specification Page
123456789
COL x x x x x x x x Temperature collector 1 15
COL 1 x Temperature collector 1 15
TST x x Temperature tank 1 15
TSTU x x x x Temperature tank 1 below 15
TST1 x x x Temperature tank 1 below 15
TSTO x x x x x Temperature tank 1 at the top 15
TST2 x x x Temperature tank 2 below 15
TFSB x Temperature solid hot fuel boiler 15
TRET x Temperature heating circuit 15
COL2 x Temperature collector 2 15
S3 x Temperature sensor 3 15
TRF   Temperature return sensor 15
S4     x x Temperature sensor 4 15
hP x x x x Operating hours relay 1 16
h P1 x x x x x Operating hours relay 1 16
h P2 x x x x x Operating hours relay 2 16
kWh     Heat quantity kWh 16
MWh     Heat quantity MWh 16
time x Time 15
Arr 1-9 System 12
DT O x x x x x x Switch-on temperature diff 17
DT1O x x x Switch-on temperature diff 1 17
DT F x x x x x x Switch-off temperature diff 1 17
DT1F x x x Switch-off temperature difference 17
S MX x x x x x x Maximum temperature tank 1 17
S1 MX x x x Maximum temperature tank 1 17
DT2O x x x Switch-on temperature difference 2 17
DT2F x x x Switch-off temperature difference 2 17
S2MX x x x Maximum temperature tank 2 17
EM x x x x x x x x emergency temperature collector 1 18
EM1 x emergency temperature collector 1 18

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Channel Arr Specification Page
123456789
OCX x x x x x x x x option collector cooling collector 1 18
OCX1 x option collector cooling collector 1 18
CMX x* x* x* x* x* x* x* x* maximum temperature collector 1 18
CMX1 x* maximum temperature collector 1 18
OKN x x x x x x x x option minimum limitation collector 1 18
OKN1 x option minimum limitation collector 1 18
CMN x* x* x* x* x* x* x* x* minimun temperature collector 1 18
CMN1 x* minimun temperature collector 1 18
OCF x x x x x x x x option antifreeze collector 1 18
OCF1 x option antifreeze collector 1 18
CFR x* x* x* x* x* x* x* x* antifreeze temperature collector 1 18
CFR1 x* antifreeze temperature collector 1 18
EM2 x emergency temperature collector 2 18
OCX2 x option collector cooling collector 2 18
KMX2 x* maximum temperature collector 2 18
OCN2 x option miminum limitation collector 2 18
CMN2 x* minium temperature collector 2 18
OCF2 x option antifreeze collector 2 18
CFR2 x* antifreeze temperature collector 2 18
PRIO x x x priority 19
tST x x x stop time 19
tRUN x x x Ciruclation time 19
OREC x x x x x x x x x option reccoling 19
O TC x x x x x x x x x option tube collector 19
DT3O x x switch-on temperature difference 3 17
DT3F x x switch-off temperature difference 3 17
MX3O x x switch-on treshold for maximum temp. 17
MX3F x x switch-off treshold for maximum temp. 17
MN3O x x switch-on treshold for minimum temp. 17
MN3F x x switch-off treshold for minimum temp. 17
AH O x switch-on temp. for thermostat 1 20
AH F x switch-off temp. for thermostat 1 20
OHQM x x x x option WMZ 16
FMAX     maximum flow 16
MEDT     antifreeze type 16
MED% MEDT MEDT MEDT MEDT antifreeze content 16
t1 on x Switch on time 1 thermostat 20
t1 off x Switch off time 1 thermostat 20
t2 on x Switch on time 2 thermostat 20
t2 off x Switch off time 2 thermostat 20
t3 on x Switch on time 3 thermostat 20
t3 off x Switch off time 3 thermostat 20
HND1 x x x x x x x x x manual operation relay 1 20
HND2 x x x x x x x x x manual operation relay 2 20
LANG x x x x x x x x x Language 20
UNIT x x x x x x x x x Change over °FAH / °CEL 20
PROG XX.XX program number
VERS X.XX version number

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4.1.1 Indicataion of collector temperatures
Shows the current collector temperature.
•COL : collector temperature (1-collector-system)
•COL1: collector temperature 1
•COL2: collector temperature 2
COL, COL1, COL2:
Collector temperature
display range: -40 ...+480°F
4.1.2 Indication of tank temperatures
Shows the current tank temperature.
•TST : tank temperature (1-tank-system)
•TSTL : tank temperature lower
• TSTU : tank temperature above
•TST1 : temperature tank 1
• TST2 : temperature tank 2
TST,TSTL,TSTU,
TST1,TST2:
Tank temperatures
Display range: -40 ...+480 °F
4.1.3 Indication of sensor 3 and sensor 4
Shows the current temperature of the corresponding addi-
tional sensor (without control function).
•S3 : temperature sensor 3
•S4 : temperature sensor 4
Please note:
S3 and S4 are only shown if the temperature sensors are
connected.
S3, S4:
S3, S4:
Sensor temperatures
Display range: -40 ...+480 °F
4.1.4 Indication of other temperatures
Shows the current temperature of the corresponding
sensor.
•TFSB : temperature solid fuel boiler
•TRET : temperature heating reverse raising
•TRF : temperature return flow
TFSB,TRET,TRF:
other measured temperatures
Display range: -40 ...+480 °F
4.1.5 Time
In this channel the current time is indicated.
By pressing button for 2 seconds the hours, by pressing
it again the minutes are displayed blinking. The time can
be set by buttons 1 and 2 and saved by pressing the
button.

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4.1.7Heatquantitybalancing
OHQM:Heat quantity measu-
rement
Adjustment range: OFF ...ON
Factory setting: OFF
A heat quantity balancing is possible for the basic systems
(Arr) 1, 3, 4 and 5 in conjunction with a flowmeter. You
just have to activate the option heat quantity balancing in
channel OHQM.
The volume flow readable at the flowmeter (l/min) must
be adjusted in the channel FMAX. Antifreeze type and
concentration of the heat transfer medium are indicated on
channels MEDT and MED%.
Type of antifreeze:
0 : water
1 : propylene glycol
2 : ethylene glycol
3 : Tyfocor®LS / G-LS
The heat quantity transported is measured by the indica-
tion of the volume flow and the reference sensor of feed
flow S1 and return flow T-. It is shown in kWh-parts in the
indication channel kWh and in MWh-parts in the indication
channel MWh. The sum of both channels form the total
heat output.
The heat quantity added up can be reset.As soon as one of
the display channels of the heat quantity is selected, symbol
is permanently shown on the display.The SET (3) button
must pressed for approx.2 seconds in order to get back into
the RESET-mode of the counter.The display-symbol is
blinking and the value for heat quantity will be set to 0. In
order to finish the RESET-procedure, the button must
be pressed in order to confirm the data.
In order to interrupt the RESET-procedure, no button
should be pressed for about 5 seconds.The controller re-
turns automatically into the indicaton mode.
FMAX: Volume flow in
l/min
Adjustment range 0 ... 20
in steps of 0,1
Factory setting 6,0
kWh/MWh:Heat quantity
in kWh / MWh
Display channel
MEDT: antifreeze
Adjustment range 0 ...3
Factory setting 1
MED%: Concentration of
antifreeze in (Vol-) %
MED% is blinded out by
MEDT 0 and 3.
Adjustement range 20 ...70
Factory setting 45
4.1.6 Operating hours counter
The operating hours counter adds up the solar operating
hours of the respective relay (hP/ h P1 / hP2). Full hours
are shown on the display.
After the operating hours are added up, they can be reset.
As soon as one operating hours channel is selected, symbol
is permanently shown on the display. The button SET
(3) must pressed for approx. 2 seconds in order to get back
into the RESET-mode of the counter. The display-symbol
is blinking and the operating hours will be set to 0. In
order to finish the RESET-procedure, the button must
be pressed in order to confirm the data.
In order to interrupt the RESET-procedure, don’t press any
button for about 5 seconds.The controller returns auto-
matically into the indication mode.
h P / h P1 /h P2:
operating hours counter
Indication channel

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4.1.8∆T-regulation
DT O / DT1O / DT2O /
DT3O:
Switch on temperature diff.
Adjustment range 2,0...40,0°Ra
Factory setting 12,0°Ra
DT F / DT1F / DT2F /DT3F:
Switch-off temperature diff.
Adjustment range 1,0...38,0°Ra
Factory setting 8,0°Ra
4.1.9Tankmaximumtemperature
If the adjusted maximum temperature is exceeded,a further
loading of the tank is stopped so that a damaging overheating
can be avoided.If the maximum tank temperature is exceeded,
symbol is shown on the display.
Please note: The controller is equipped with a security-
switch-off of the tank, which avoids a further loading of the
tank if 295°F is reached at the tank.
S MX / S1MX /S2MX:
Maximum tank temp.
Adjustment range -40...+480°F
Factory setting -140°F
First the controller works in the same way as a standard
differential controller. If the switch-on difference (DT O /
DT1O /DT2O) is reached, the pump is activated. If the
adjusted switch-off temperature is underrun (DTF /DT1F
/DT2F), the controller switches-off.
Maximum temperature limitation
The controller is equipped with an independent tempe-
rature differential regulation for which minimum and
maximum temperature limations as well as corresponding
switch-on and -off temperatures can be separately adjusted.
Only possible for Arr = 2 and 8 (e.g. for solid fuel boilers or
heat exchange regulation).
If the adjusted value MX3O is exceeded, relay 2 will
be deactivated. When falling below MX3F, the re-
lay will be switched on again.
Reference sensor:
S3 by Arr 8 (TSTU)
S4 by Arr 2 (TST2)
Is the adjusted value MN3O underrun, relay 2 will be
deactivated. By falling below MN3F, the relay will be
switched on again.
Reference sensor:
S4 by Arr 8 (TFSB)
S3 by Arr 2 (TSTU)
Both switch on- and switch off temperature differences
DT3F and DT3O apply parallely for the maximal- and
minimal temperature limit.
MX3O / MX3F:
Maximum temperature limi-
tation
Adjustment range 30...205°F
Factory setting
MX3O 140°F
MX3F 136°F
Minimum temperature limitation
MN3O / MN3F:
Minimum temperature limi-
tation
Adjustment range 30...195°F
Factory setting:
Arr = 2
MN3O 40°F
MN3F 50F
Arr = 8
MN3O 140°F
MN3F 150°F
4.1.10 ∆T-controller(solid fuel boiler and heat exchange)
Please note:Switch-on temperature difference DT O must
be at least 2 °Ra higher than the switch-off temperature-
difference DF.

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CMN / CMN1 / CMN2:
col. minimum temperature
Adjustment range 50...195°F
Factory setting 50°F
CMX / CMX1 /CMX2:
collectormaximumtemperature
Adjustment range 210...380°F
Factory setting 250°F
4.1.12System cooling If the adjusted maximum tank temperature is reached, the
solar system switches-off. If now the collector temperatu-
re rises to the adjusted maximum collector temperature
(CMX / CMX1 /CMX2), the solar pump remains activa-
ted until this temperature limitation value is again underrun.
The tank temperature might continue to rise (subordinated
active maximum tank temperature), but only up to 400°F
(emergency shutdown of the tank). If the tank temperature
is higher than the maximum tank temperature (S MX /
S1MX / S2MX) and the collector temperature is by at
least 10°RA lower than the tank temperature, the solar
system remains activated until the tank is cooled down again
by the collector and the tubes below the adjusted maximum
temperature (S MX / S1MX / S2MX)(only by activated
OREC function).
In case of an activated system is shown on the display
(blinking). Due to the cooling function, the solar system can
be kept operable for a longer period on hot summer days
and a thermal release of the collector and the heat transfer
medium is ensured as well.
OCX / OCX1 /OCX2:
Option System cooling
Adjustment range OFF...ON
Factory setting OFF
4.1.13Option collector minimum limitation
OCN / OCN1 /OCN2:
collector minimum limitation
OFF / ON
Factory setting OFF
The minimum collector temperature is a minimum switching
temperature which must be exceeded so that the solar
pump (R1/R2) is switched-on. The minimum temperature
shall avoid a steady starting-up of the solar pump (or solid
fuel boiler charging pumps) for low collector temperatures.
If the minimum temperature is underrun, is shown on
the display (blinking).
CFR / CFR1 / CFR2:
antifreeze temperature
Adjustment range 15...50°F
Factory setting 40°F
4.1.14Option antifreeze
OCF / OCF1 /OCF2:
antifreeze function
Adjustment range OFF / ON
Factory setting OFF
4.1.11 Collector temperature limitation
Emergency shut down of the collector
If the adjusted collector limit temperature (EM / EM1 /
EM2) is exceeded the solar pump (R1/R2) is deactivated
in order to avoid a damaging overheating of the solar
components (collector emergency shutdown).The factory
setting for the temperature limitation is 285°F - it can be
changed within the adjustment range of 230 ...400°F.Symbol
is shown on the display (blinking).
EM / EM1 / EM2:
temperature limitation corector
Adjustment range 230...400°F
Factory setting 285°F
The antifreeze function activates the loading circuit between
collector and tank if the adjusted antifreeze function is un-
derrun in order to protect the medium against freezing or
„thickening“. If the adjusted frost protection temperature is
exceeded by 2°F, the loading circuit will be deactivated.
Please note:
As there is only a limited heat quantity of the tank available
for this function,the antifreeze function should only be used
in regions with few days of temperatures around freezing
point.

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19|
The controller checks the tanks regarding loading facilities
(switch-on difference). If the priority tank cannot be loaded,
the lower-ranking tank is checked. If the lower-ranking tank
can be charged this is effected by the so-called „oscilating
charge time“ (tRUN).When the oscillating charge time is
over the loading is stopped. The controller regulates the
increase of the collector temperature. If it increases by the
collector rising temperature (∆T-Col 4°Ra, fixed software
value), the expired break time is again reset to zero and the
oscillating break time starts again. If the switch-on conditions
of the priority tank are not reached, the loading of the
lower-ranking tank is continued. If the priority switch has
reached its maximum temperature, the oscillating charge is
not effected.
Oscillating break time / oscillating charge time /
collector rising temperature
4.1.17 Tube collector special function If the controller measures an increase of 4°Ra compared
to the collector temperature stored at last, the solar pump
is switched-on to 100 % for about 30 seconds. After the
expiration of the solar pump runtime the current collector
temperature is stored as a new reference value. If the
measured temperature (new reference value) is again
exceeded by 4°Ra, the solar pump again switches-on for 30
seconds. If the switch-on difference between collector and
tank is again exceeded during the runtime of the solar pump
or the standstill of the system, the controller automatically
switches over to solar charging.
If the collector temperature drops by 4°Ra during standstill,
the switch-on value for the special tube collector function
will be recalculated.
O TC:
Tube collector special function
Adjustment range: OFF ...ON
Factory setting: OFF
4.1.16 Recooling function If the adjustem maximum tank temperaute (S MX, S1MX,
S2MX) is reached, the solar pump remains activated in
order to avoid an overheating of the collector. The tank
temperature might continue to increase but only up to
205°F (emergency shutdown of the tank).
In the evening the solar system continues running until
the tank is cooled down to the adjusted maximum tank
temperature via collector and pipes.
OREC:
option recooling
adjustment rangeOFF ...ON
Factory setting: OFF
4.1.15 Oscillating charge
Respective adjustment values:
Factory setting Adjustment range
priority [PRIO] (1 / Arr 5,6) (2 / Arr 4) 0-2
oscillatingbreak-time[tST] 2 min. 1-30 min.
oscillatingcharge-time[tRUN] 15 min. 1-30 min.
Die iSolar Plus 24V priority logic The above-mentioned options and parameters only have
a meaning in multi-tank systems (system Arr = 4, 5, 6). If
priority 0 is adjusted, the tanks which show a temperature
difference towards the collector are loaded in numerical
order (tank 1 or tank 2). Usually only one tank is loaded at
this point. For Arr= 5, 6 parallel loading is also possible.
priority:

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For control- and service works the operating mode of
the controller can be manually adjusted by selecting the
adjustment value MM in which the following adjustments
can be made:
4.1.19 Operatingmode
• HND1/HND2
Operating mode
OFF : relay off (blinking) +
AUTO : relay in automatic operation
ON : relay on (blinking) +
HND1/HND2:
Operating mode
Adjustment range:
OFF,AUTO,ON
Factory setting:AUTO
The thermostat function works independently from the
solar operation and can e.g. be used for the use of surplus
energy or after-heating.
• AHO< AHF
the thermostat function is used for after-heating
• AHO > AHF
the thermostat function is used for use of surplus
energy
Symbol will be shown on the display if the second
relay output is activated.
4.1.18Thermostat function (Arr = 3)
Afterheating
AHO:
Thermostat-
switch-on temperature
Adjustment range 30...205°F
Factory setting 105°F
AHF:
Thermostat-
switch-off temperature
Adjustment range 30...205°F
Factory setting 115°F
t1 E, t2 E, t3 E:
Thermostat switch-on time
Adjustment range:
00:00 ...23:45
Factory setting: 00:00
t1 A, t2 A, t3 A:
Thermostat switch-off time
Adjustment range:
00:00 ...23:45
Factory setting: 00:00
In order to block the thermostat function for a certain
time span, there are 3 time frames t1 ...t3. If the function
should be activated only between e.g. 6:00 and 9:00, 6:00
should be set for t1 E and 9:0 should be set for t1 A.The
factory setting for the thermostat function is in continuous
operation.
If all time frames should stop at 00:00 o’ clock, the thermo-
stat function is continuously in operation
(factory setting).
4.1.20 Language
The menu language can be adjusted in this channel.
• dE : German
•En : English
• It : Italiano
•Fr : French
LANG:
Adjustment of language
Adjustment range: dE,En, It, Fr
Factory setting: En
use of surplus energy
4.1.21 Unit
The menu unit can be adjusted:
• °FAH
•°CEL
UNIT:
Adjustment of unit
Adjustment range: FAH, °C
Factory setting: FAH