Kera SRK868V6 User manual

System Controller for Solar Heating
Model SRK868V6
Installation and Operation Instructions

Solar Controller SRK868V6 Installation and Operation Instructions
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Solar Controller Kit
Kit Contents:
Item PCS Description
1 1 Control Panel with LCD display and Control Key Pad
2 1 Power Module with Wiring Terminal strip
3 2 NTC Temp. Probes for Water Tank ( upper and lower )
4 1 NTC Temp. Probe for Hot Water Pipe ( Optional )
5 1 PT1000 Temp. Probe for Solar Panel
6 1 Mounting and wiring hardware
7 1 Installation and Operation Instructions manual
Features:
•Suitable for most types of Solar Heating systems
•Internal real time Clock with backup
•3 temperature sensor probes + 1 optional
•1 Output for Solar panel circulating pump
•1 Outputs for User Hot Water pipe circulating pump
•1 High Power Output for water tank Booster Heating
•1 Output for optional valve for overheat cooling
•Programmable Temperature Differential on the Solar Collector
•Programmable Water Tank Temperature and Time for the tank booster heating
•Programmable Time ( of day ) and Temp. for User Hot Water pipe circulation
•Programmable Tank overheat protection
•Programmable Solar Collector freeze protection with reheating
•Monitoring and display off all temperature sensors readings

Solar Controller SRK868V6 Installation and Operation Instructions
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Control Panel
Item Description
1 Green lamp Supply Power ON indicator
2 ON/OFF pushbutton Controller ON/OFF switch ( and special functions )
3 “▲” ”▼” Adjust Adjustment UP, DOWN buttons
4 ▲T Solar Temperature Difference preset mode
5 Manual ▲T Manual ON/OFF switching of Solar circulating pump (P1)
6 OK Activate / Deactivate selected function
7 oC / oF Celsius / Fahrenheit selection
8 SET Start of Programming modes or activation of special functions
9 Pipe timing Timer Programming mode for Hot Water pipe circulating pump (P2)
10 Recovery Reset the display to factory default settings
11 Temp. Display Display the temperature readings
12 Clock Set the Clock
13 Heating Auto Time/Temperature Program and Manual control of Booster Heat
14 “◄” “►”Transfer Cursor control during preset
15 Display screen LCD display with LED backlight

Solar Controller SRK868V6 Installation and Operation Instructions
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INDEX
page
1.Safetyinformation 5
2.Installation 6
2.1 Control Panel installation 6
2.2 Power Module installation 6
2.2.1 Wall adaptor plate 6
2.2.2 Wiring 6
3. System Setup and Operation 8
3.1 ON /OFF button operation 8
3.2 Clock preset 8
3.3 Manual operation 9
3.4 Temperature display 9
3.5 System configuration examples 9
3.5.1 Configuration A 9
3.5.2 Configuration B 10
3.6 Differential Temperature control 10
3.7 Programmable, Temperature controlled heating booster 11
3.8 Time controlled user Hot Water circulation 12
3.9 Temperature controlled user Hot Water circulation 12
3.10 Anti Freeze protection 13
3.11 High temperature protection ( mode 1) 13
3.12 High temperature protection ( mode 2) 14
3.13 “oC/oF” button 14
3.14 System protection features 14
4. Trouble shooting 15
4.1 Error protection 15
4.2 Error messages 15
4.3 Preventing potential errors 15
5.Specifications 17

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1. Safety information
•When laying cables, please ensure that no damage occurs to any of the safety installations in the building.
•The controller must not be installed in rooms with flammable gasses or materials.
•Make sure that the environmental conditions do not exceed the controller and other systems specifications.
•Before connecting the device, make sure that the Power Supply Line specifications match the controller.
•All devices connected to the controller must conform to the technical specifications of the controller.
•All installation must be performed ONLY when ALL POWER is disconnected. All local work and safety regulations must
be followed. Wiring or any operations that require opening of electrical enclosures (e.g. even changing the fuse) should
be performed by qualified personnel.
•Installation, electrical wiring, setup and maintenance of the device should be performed by trained, professional
personnel familiar with this manual and should follow the instructions contained herein.
The manufacturer cannot monitor the compliance with these instructions or the circumstances and methods used during
installation, operation and maintenance of this controller. Improper installation can cause damage to people and equipment.
Therefore, the manufacturer and the retailer are not liable for any losses, damages or cost that might arise due to improper
installation, operation or use and maintenance of the system.
If it becomes evident that safe operation is no longer possible (for instance visible damage), please make sure that the
system is powered OFF and deactivated immediately.
Note: Ensure that the device cannot be accidentally put into operation.
The manufacturer reserves the right to make changes to the product, technical specifications or installation and operation
instructions without prior notice.

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2. Installation
2.1 Control Panel Installation
►Separate the back panel from the display using a screwdriver as shown in Pic. 1
►Fix the back panel on the wall using screws, see Pic. 2
►Reinsert the face of the display into the latches in the back panel, see Pic. 3
2.2 Power Module Installation
2.2.1 Wall adaptor plate
►Mark the holes position on the wall (Pic. 4)
►Install the anchors and fasten the adaptor plate with screws (Pic. 4)
►Hang the Power Module on the adaptor plate
2.2.2 Wiring
Disconnect ALL Power supply before opening the
enclosure !
All guidelines and local safety regulations must be
observed.
►To access the wiring compartment, loosen the screws (1,2) and
remove the smaller terminal cover. ( Pic. 5 )
Fixing hole
Pic. 1 Pic. 2 Pic. 3
Pic. 4
Pic. 5

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The Supply Power or the load power should
ONLY be switched ON when the housing of
the controller is CLOSED and secured.
Make sure that the wiring and the enclosure
are not damaged.
If needed, the thin plastic tabs in the wall of the
terminal compartment cover may be broken off
to facilitate routing of the wires (See Pic. 6) .
•Wiring Terminals ( see Pic. 7)
Pic. 7
Abbreviation Function
T1 Solar Collector temperature sensor T1
T2 Tank temperature sensor T2, (Tank bottom)
T3 Tank temperature sensor T3 (Tank top)
T4 (Optional) User Hot Water pipe temperature sensor
3-core wire to Display 3-conductor cable Connection to Control Panel
Power Power Supply Line
Heating Output to control the Booster heating H1
▲Ton/▲Toff To Solar circulating pump P1
Pipe circulation To User Hot Water circulating pump P2
Electromagnetic Valve To activate Tank high temperature protection valve (R1)
Pic. 6

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Inputs
1. Inputs T1, T2 and T3 (T4 optional)
for temperature sensors wiring
2. 3-cond. cable connected to the
Control Panel
Outputs
1. Outputs P1 and P2: electromagnetic
relays
max. Switching current: 5A
2. Output H1: electromagnetic relay,
max switching current 16A
3. Output R1: electromagnetic relay,
max switching current 5A
Power Supply connection
1. Make sure that the
Power Line voltage is
as specified for the
controller model
System Reset: This button is located above the screw terminals. Press to RESET the entire system to the factory settings.
NOTE: Installation of the temperature sensors:
Only the originally supplied Pt1000 temperature sensor should be used at the Solar collector. It has high temperature
silicon jacketed cable that is suitable for all weather conditions. This temperature sensor and the cable can withstand
temperatures up to +280oC (+536F). There in NO positive and negative polarity on the sensor connections.
Only the originally supplied NTC10K, B=3950 temperature sensors should be used at the tank and hot water pipe locations.
They have PVC jacketed cable, that is temperature resistant up to +105oC (+221F). There is NO positive or negative
polarity on the sensors connections.
All sensor cables carry low voltage, and must not be laid close to any high voltage wiring like 120, 230 or 400-volt wiring. A
minimum separation of at least 100 mm (4”) is required.
If external electromagnetic fields are present, e.g. from heavy current cables, overhead train cables, transformer
substations, radio and transmitters, radio stations, microwave devices etc, then the sensor cables may have to be
adequately shielded.
The Sensor cables may be extended to a maximum length of appx. 100 meters ( 300 feet ). The longer the cable, the
heavier (thicker) the cable gauge should be used.
3. System Setup and Operation
Remember to connect the sensors and the pumps to the controller before connecting the Power supply !
After switching on the power to the controller, first set the controller “clock”.
Note, that the control panel LCD display has a back light that can turn itself off after appx. 30 minutes of not using
any pushbuttons. The backlight will be reactivated immediately upon pressing of any button on the panel.
3.1 ON / OFF button operation
►Press and hold the “ON/OFF” button for 3 seconds. The entire controller will be deactivated but the tank temperature (T2)
and current time ( clock ) will remain displayed on the screen.
When the “ON/OFF” button is pressed again, the controller will be reactivated.
3.2 Clock preset
After power is switched on for the first time, the display will show the clock time as: “00:00”.
►Press the “Clock” button. The clock hours will flash
►Press “▲”“▼” buttons to set the current hour.
►Press the “Clock” button again. The clock minutes will flash
►Press “▲”“▼” buttons to set the current minutes.
After 6 seconds the controller will store the setting automatically.

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3.3 Manual operation
When powering up the controller for the first time, or during testing, the outputs of the controller may be operated manually
as follows:
•Manual operation of the Solar Panel Pump (P1)
►Press the “Manual ▲T” button. The solar circulation pump (P1) will be switched ON. The display will indicate this status.
►Press the “Manual ▲T ” button again. The solar circulation pump (P1) will be switched OFF or the program will
deactivate it after 10 minutes automatically.
•Manual operation of the Hot Water circulating pump (P2)
►While the Supply Power is on, press the “ON/OFF ” button to activate the hot water pipe circulation pump (P2). The
display will indicate this status.
►Press the “ON/OFF ” button again to shut-off this pump or the program will deactivate it after 3 minutes automatically.
•Manual operation of the Heating booster (H1)
►Press and hold the “Heating ” button for 6 seconds. The booster heating output (H1) will be switched ON.
►Press the “Heating” button again to turn OFF this output immediately.
3.4 Temperature display
►Press the “Temp. Display” button repeatedly to review the current temperature readings for: the collector (T1), tank
bottom (T2), tank top (T3) and the hot water pipe circulation sensor (T4).
The temperature of the tank bottom sensor (T3) is displayed automatically when no operation is performed for at least 6
seconds.
3.5 System configuration examples
3.5.1 Configuration A: 1 Collector array + 1 Storage tank + 1 Pump ( with 1 Sensor in the water tank )
Description:
The solar pump (P1) is turned ON when the switch-ON
temperature difference between the collector array (T1)
and the storage tank (T2) is reached. When the
temperature difference between the collector array (T1)
and the storage tank (T2) drops below the switch-OFF
temperature difference, the solar pump (P1) is turned
OFF.
T1: Temperature sensor in the solar collector
T2: Temperature sensor in the bottom part of tank (for
solar circulation and optional heating booster control ).
P1: Solar circulating pump
P2: ( Optional ) User hot water circulating pump
Notes:
H1: Terminals for connecting to the optional tank heating
booster.
T4: Optional temperature sensor of the user hot water.

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3.5.2 Configuration B: 1 Collector array + 1 Storage tank + 1 Pump ( with 2 Sensors in the water tank )
Description:
The solar pump (P1) is activated when the switch-ON
temperature difference between the collector array (T1)
and the storage tank (T2) is reached. When the
temperature difference between the collector array (T1)
and the storage tank (T2) drops below the switch-OFF
temperature difference, the solar pump (P1) is turned
OFF.
T1: Temperature sensor in the solar collector
T2: Temperature sensor in the bottom part of the tank (for
solar circulation).
T3: Temperature sensor in the top part of the tank (for
optional heating booster).
P1: Solar circulating pump.
P2: ( Optional ) User hot water circulating pump.
Notes:
H1: Terminals for connecting to the optional tank heating
booster.
T4: Optional temperature sensor of the user hot water
pipe.
T3: If the sensor T3 is damaged or not installed, the
controller will use the signal from the sensor T2 instead,
for the control of the heating booster.
3.6 Differential Temperature control
Functional description:
The Solar panel pump P1 is controlled by the temperature difference. As long as the temperature difference between the
collector and the tank is higher than the preset value, this pump remains ON.
For example: If the switch-ON temperature difference is set to 8oC (14F), and the switch-OFF temperature difference is
4oC (7F), then for instance:
When the temperature in the bottom part of the tank is +20oC (+68F), the collector temperature must rise above +28oC
(+82F) to turn ON the pump P1, and the pump will be switched OFF when the temperature falls below +24oC (+75F).
Important information: The controller default switch-ON temperature difference is set to 8oC (14F) and the switch-OFF
difference is set to 4oC (7F). These are usual standard solar system recommended settings. They should be altered only in
special applications like for instance in very large systems.
Note: To prevent errors, the controller minimum differential (∆Ton - ∆Toff ) is limited to 2oC ( 4F ).
Setup procedure:
►Press the “▲T” button. The temperature display will flash.
►Press “▲” “▼” button to adjust the switch-ON temperature
difference. Adjustable range: 2oC to 15oC (4F to 27F). The default
value = 8oC (14F).
►Press the “▲T” button again.
►Press “▲” “▼” button to adjust the switch-OFF temperature
difference. Adjustment range:
0oC (0F) to [▲Ton - 2oC (4F)]. The default value = 4oC (7F).
After 6 seconds, the controller will lock-in the setting.

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3.7 Programmable, Temperature controlled Heating Booster for UP TO 3 periods per day
The solar controller can be combined with an optional heating booster that can automatically control the tank water
temperature during the time periods for heating. During these ( up to ) 3 programmed periods of the day the heating booster
output (H1) is activated when the temperature (T3), usually located at the top part of the tank, is 6oC (11F) below the
programmed switch-OFF temperature. When T3 exceeds or equals the preset temperature, this output is turned OFF.
Setup steps:
►Press the “Heating” button. The time will flash.
►Press “▲” “▼” button to set the ON hours
►Press“←”、“→” button to shift to the ON minutes
►Press “▲” “▼” to set the minutes
►Press “←”、“→” again to shift to the OFF temperature preset
►Press “▲” “▼” to set the OFF temperature value
►Press “Heating” button again to set the OFF time
►Press “▲” “▼” button to set the OFF hours
►Press“←”、“→” button to shift to the OFF minutes
►Press “▲” “▼” to set the minutes
•After 6 seconds, the controller will lock-in the settings.
•Repeat the above steps three times for the 3 different periods per day. The number (1-3) on the display will indicate the
time period being preset.
•Default settings:
- 1-st heating period: From 4:00 AM (ON) till 5:00 AM (OFF)
- 2-nd heating period: the booster is deactivated. The settings are 10:00 AM (ON) till 10:00 AM (OFF)
- 3-rd heating period: 5:00 PM (ON) till 10:00 PM (OFF)
NOTE: The Default OFF temperature for the booster is 55oC (131F).
NOTES:
•To turn OFF the heating booster for one of the 3 periods, set the ON (start) time and the OFF (stop) time to the same
time.
•Pressing the “Heating” button will display the programmed settings.
MANUAL operation:
To turn ON the booster heating (H1) manually, press the “HEATING” button 3 times while the temperature T3 is lower than
+50oC (+131F).
To turn OFF the heating manually, press the button again once.
The booster heating control output will be automatically switched OFF when the temperature (T3) reaches +55oC (+131F).
Note: The heating booster output (H1) is active when this symbol is shown on the display.

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3.8 Time controlled user Hot Water circulation for UP TO 3 periods per day
The controller can be programmed for up to 3 periods of each day to activate the P2 output that can be used to control a
pump to circulate the hot water in the user hot water pipe. During each of the programmed time periods the pump control
output (P2) will be switched ON for 3 minutes and then OFF for 15 minutes. This sequence will continue throughout each of
the 3 preprogrammed periods of each day.
Setup procedure:
►Press the “Pipe timing” button to set the START time of
circulation. The time will flash.
►Press “▲”“▼” button to adjust the START hour
►Press “←”、“→” button to go to minutes
►Press “▲”“▼” button to adjust the START minutes
►Press the “Pipe timing” button again to set the END time of
circulation
►Press “▲”“▼” button to adjust the END hour
►Press “←”、“→” button to go to minutes
►Press “▲”“▼” button to adjust the END minutes
After 6 seconds, the controller will lock-in the settings.
Perform the above procedure for all three time period for the day. A number 1-3 displayed on the screen to indicate the
preset time period.
NOTES:
•To turn OFF the timed circulation for one of the 3 periods, set the ON (start) time and the OFF (stop) time to the same
value.
•During normal operation, pressing the “Pipe timing” button will display the programmed settings.
Manual operation:
During normal operation, the hot water circulation pump control output (R1) can be turned ON manually by pressing the
“ON/OFF” button. The “Pipe circulation” symbol will be displayed and the R1 output will be activated for a 3 minute period,
then it will stop automatically.
To stop the pump P2 manually, press the “ON/OFF” again.
3.9 Temperature controlled user Hot Water circulation
Note: T4 sensor is not included with the standard controller. The user needs to have an extra temperature sensor T4 to be
able to use this function.
The controller can provide a temperature-controlled hot water circulation function. This function needs an extra hot water
circulation pump ( P2) and a sensor (T4), which should be placed on the house hot water return pipe. When the
temperature sensed by the sensor T4 is lower than the preset ON temperature, the hot water circulation pump (P2) is
activated and works until the temperature exceeds the OFF temperature.
For instance: if the preset ON temperature is 40oC, then when T4 is lower than 40oC, the P2 pump is activated and it will be
turned OFF when the temperature is higher than 45oC.
To Enable / Disable this function:
►Press the “SET” button 2 times. The hot water circulation
temperature setting will flash. The default setting is “OFF” indicated
on the display as: “-- --”.
►Press “OK” button to activate this function.
►Press “▲”“▼” button to adjust the temperature of circulation
pump.
Adjustable range: 20oC(68F) to 50oC (122F).
After 6 seconds, the controller will lock-in the settings.
►To deactivate this function press “OK” button while in the
circulation temperature preset mode. The display will indicate: “ -----“ .

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IMPORTANT NOTE: Do not set the time period that cross over the 24:00 hrs (12 midnight ). The controller may not
schedule the timing properly.
Note:
•The Temperature controlled hot water circulation function has higher priority than the Time controlled hot water
circulation function.
•If the Temperature controlled hot water circulation function is deactivated, then the Time controlled hot water circulation
function is activated automatically.
•The location of the sensor T4 should be at least 1.5m (5 Ft) away from the tank in order to prevent undesired operation.
3.10 Anti Freeze protection
Note: this function should only be used in systems that do not use anti-freeze liquid.
A) If this function is enabled, the solar pump control output (P1) will be switched ON when the temperature of the collectors
(T1) falls below the preset ON temperature of the anti-freeze protection.
When the collector temperature T1 rises 5oC (9F) higher than the preset ON temperature of the freeze protection, the
controller will turn OFF the solar pump output (P1).
B) If this function is enabled and the tank temperature (T2) falls below +10oC (+50F), the heating booster output (H1) will
be switched ON automatically and it will be switched OFF when the water temperature (T2) rises above +15oC (59F).
To Enable / Disable this function:
►Press the “SET ” button once. The freeze protection temperature
setting will flash.
(The default setting is OFF, display: “-- --“ )
►Press the “OK” button to enable this function.
►Press “▲” “▼” button to adjust the switch-ON temperature of the
freeze protection.
Adjustment range: +2oC to +10oC (+36F to +50F).
After 6 seconds, the controller will lock-in the settings.
►To disable this function, press the “OK” button while the function is enabled. The display will show: “-- --“.
This symbol on the display indicates that the high temperature protection (1) is enabled.
NOTE: In areas where freezing temperatures occur often, we suggest that a solar system with anti-freeze liquid be used
rather than water as the heat exchange medium.
3.11 High temperature protection ( mode 1 )
this mode operates in order to prevent overheating of the water in the tank, the controller checks the temperature of the
tank on T2 sensor. When T2 rises above +95oC (+203F), the solar pump (P1) is deactivated. When the temperature T2
drops below +85oC (+185F), the system returns to normal operation.
Note: This function default parameters are permanently preset and cannot be altered by the user.
This symbol on the display indicates that the high temperature protection (1) is enabled.

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3.12 High temperature protection ( mode 2 )
Note: this function is only useful in the solar systems that use a tank with two heat exchangers.
In this mode, an optional, external valve should be installed on the water tank hot water outlet pipe and connected to the R1
output. The controller will check the tank temperature on the sensor T2. If T2 temperature is higher than the preset
Maximum temperature for this function, the valve control output (R1) will be switched ON.
When T2 drops 5oC (9F) below the Maximum temperature, the R1 output will be switched OFF.
To Enable / Disable this function:
►Press the “SET” button 3 times.
The maximum tank temperature setting will flash.
(The default setting is OFF, display: “-- --“)
►Press the “OK” button to activate this function.
►Press “▲”“▼” button to adjust the maximum temperature.
Adjustment range: +80oC to +99oC (+176F to +211F).
After 6 seconds, the controller will lock-in the settings.
►To disable this function press the “OK” button while in the Maximum temperature preset mode.
The display will indicate: “-- --“.
This symbol on the display indicates that the high temperature protection (mode 2) is enabled.
3.13 “oC/oF”button
►Press the “ oC/oF” button to toggle between the Celsius and Fahrenheit units.
3.14 System Protection features
A. Memory protection in case of power failure
In case of the power failure, the controller saves the settings unchanged. When the power is restored, the controller
recovers to the preset mode.
B. System Restore ( default ).
If an error or malfunction occurs in the system, press the “OK” button on the panel. The system will recover to the factory
default settings.

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4. Trouble shooting
4.1 Error protection
When an open or a short circuit is detected on the temperature sensors connection, the controller will switch OFF the
corresponding functions. At the same time an error message will be indicated on the display.
4.2 Error messages
If the control unit is not working correctly, please check the following error messages and follow the error correction
procedure.
Error messages flashing on the LCD display:
Error
message
Description Cause of error Error correction
T1
flashing
T1 sensor fault Sensor wiring open or shorted Check sensor resistance
value, replace sensor if
necessary
T2
flashing
T2 sensor fault Sensor wiring open or shorted Check sensor resistance
value, replace sensor if
necessary
T3 99oC
flashing
T3 sensor fault Sensor wiring open or shorted Check sensor resistance
value, replace sensor if
necessary
E0 Connection fault between display and
controller
Connecting cable is open or shorted Check and replace if
necessary
4.3 Preventing potential errors
Review carefully the information below. Call for the controller repair only when you are sure that none of the problems listed
below is responsible for the malfunction.
A potentially defective sensor can be tested using an Ohmmeter. To do this, the sensor wiring must be disconnected, its
resistance tested and compared with the values in the table below. A small deviation is acceptable, ( Note: Disconnect all
power before opening the case )
PT1000 resistance values
oC0 10 20 30 40 50 60 70 80 90 100 110 120
Ω1000 1039 1077 1116 1155 1194 1232 1270 1309 1347 1385 1422 1460
NTC 10K B=3950 resistance values
oC0 10 20 30 40 50 60 70 80 90 100 110 120
Ω33620 20174 12535 8037 5301 3588 2486 1759 1270 933 697 529 407

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Possible Causes of errors
Symptoms Secondary symptoms Possible cause Procedure
Controller does not appear
to function at all
Display shows nothing, no
display illumination
Controller power supply is
interrupted
Check the controller power
wiring and connection
cable between the
controller and the display.
The solar pump does not
operate despite all correct
conditions being satisfied
The pump symbol on the
display is flashing
Pump power supply is
interrupted
Check the pump power
cable
Pump does not operate The pump symbol on the
display is not flashing, error
message signal is flashing
Fault ( short circuit or open
circuit) in the temperature
sensor or its wiring
On the controller, read the
current values from all
connected temperature
sensors, replace all
defective sensors and /or
wiring
The solar pump DOES
operate despite the “ON”
conditions NOT being
satisfied
The pump symbol on the
display is flashing
The freeze protection
function is activated.
No problem, it is normal. If
necessary, disable the
corresponding functions.

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5. Specifications
•Supply：Models for 120Vac or 208-240Vac ±10%, or 12/24Vac , 50/60Hz
•Power consumption：< 4VA
•Temperature test units：Celsius or Fahrenheit ( selectable )
•Temperature test accuracy：± 1oC ( ± 2F )
•Temperature test range：0 ~ 121 oC ( 32 ~ 250 F )
•Internal Real Time Clock：Yes
•Clock backup：Internal lithium battery ( or self-recharging backup )
•Program Memory: Internal, non-volatile
•4 test Inputs：4 wired temperature sensor probes,
91 Pt1000 sensor (≤500oC) for collector (silicon cable ≤280oC),
91 or 2 NTC10K, B3950 sensors (≤135oC) for tank, (PVC cable ≤105oC),
9(optional) 1 NTC 10K, B3950 sensor (≤135oC) for hot water circul. pump (PVC cable ≤105oC),
•Inputs wiring connection: Screw terminal
•4 Outputs ( SPST, N.O. relays ):
91 for Heating booster, 16Amp, 240Vac max. ( max. 2000W resistive load )
91 for Solar circulating pump, 5Amp, 240Vac max. ( max. 600W load )
91 for Hot Water circulating pump, 5Amp, 240Vac max. ( max. 600W load )
91 for electromagnetic valve, 5Amp, 240Vac max. ( max. 600W load )
•Outputs wiring connection: Screw terminal
•Control Panel display: LCD with LED backlight
•Control Panel dimensions: 120mm x120mm x18mm
•Power Module dimensions: 200mm x140m x 45mm
•Operating ambient temperature ：-10oC ~ 50oC.
•Enclosure rating: Water proof grade IP40.