Kipp&Zonen SOLYS 2 User Manual
SOLYS 2
2-Axis Sun Tracker
Instruction Manual
IMPORTANT USER INFORMATION
Reading this entire manual is essential for full understanding of the proper use and safe
operation of this product
Should you have any comments on this manual we will be pleased to receive them at:
Kipp & Zonen B.V.
Delftechpark 36, 2628 XH, Delft, the Netherlands
P.O. Box 507, 2600 AM, Delft, the Netherlands
Phone +31 (0)15 2755210
Fax +31 (0)15 2620351
Email info@kippzonen.com
Web www.kippzonen.com
Kipp & Zonen reserves the right to make changes to the specifications without prior notice.
WARRANTY AND LIABILITY
Kipp & Zonen guarantees that the product delivered has been thoroughly tested to ensure that it meets its
published specifications. The warranty included in the conditions of delivery is valid only if the product has been
installed and used according to the instructions supplied by Kipp & Zonen.
Kipp & Zonen shall in no event be liable for incidental or consequential damages, including without limitation, lost
profits, loss of income, loss of business opportunities, loss of use and other related exposures, however caused,
arising from the faulty and incorrect use of the product.
Modifications made by the user can affect the validity of the CE declaration.
COPYRIGHT© 2011 KIPP & ZONEN
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any
form or by any means, without permission in written form from the company.
Manual version: 1112
Throughout the manual and on the SOLYS 2 instrument symbols are used to indicate to the user important
information.
The meaning of the symbols located on the SOLYS 2 is as follows:
Caution (refer to accompanying documents)
Caution, risk of electric shock
Protective conductor terminal
DC (Direct Current)
AC (Alternating Current)
The meaning of the symbols located inside the SOLYS manual 2 is as follows:
Important, indicating a point of consideration.
Caution, risk of electric shock, always connect a protected earth
Note: Useful information for the user
Tip: Useful information for the user
EC TYPE DECLARATION OF CONFORMITY
We: Kipp & Zonen B.V.
Postbus 507
2600AM Delft
The Netherlands
Declare under our sole responsibility that the product:
Type: SOLYS 2
Name: Sun tracker
To which this declaration relates is in conformity with European Harmonized Standards as published in:
Official Journal of the EC: Issue: C246 (05-10-2005)
The compliance of the product has been based on:
EN 61326-1:2000 Emissions and Immunity
EN 61010-1:2001 Safety
Following the provisions of the directive:
EMC-directive: 2004/108/EC
Electrical Safety: 65/2005/EC
These conclusions are based on test reports:
1678/SOLYS/EMC
1678/SOLYS/LVD
ce-test, qualified testing bv
Kiotoweg 363 3047BG Rotterdam
Delft,
08 February 2008
B.A.H. Dieterink
President
Kipp & Zonen B.V.
TABLE OF CONTENTS
IMPORTANT USER INFORMATION .............................................................................................................................. 1
EC Type DECLARATION OF CONFORMITY .................................................................................................................. 3
TABLE OF CONTENTS ................................................................................................................................................ 4
1 GENERAL INFORMATION ................................................................................................................................... 5
1.1 INTRODUCTION TO THE SOLYS 2 .............................................................................................................. 5
1.2 MANUAL ................................................................................................................................................... 5
2 SPECIFICATIONS OF THE SOLYS 2 .............................................................................................................. 6
3 INSTALLATION .................................................................................................................................................. 8
3.1 REQUIRED TOOLS FOR SOLYS 2 MOUNTING ............................................................................................. 9
3.1.1 REQUIRED TOOLS FOR SHADING BALL ASSEMBLY / SUN SENSOR .......................................................... 9
3.2 MINIMUM OPERATING AREA / CONSIDERATIONS ...................................................................................... 10
3.3 CREATE A FIRM BASE TO MOUNT THE TRIPOD STAND with the K&Z logo pointing East. ........................... 11
3.4 Mount the tracker on the tripod with the E on the mounting flange pointing East .................................... 12
3.5 Level the SOLYS 2 using the integrated bubble level and tripod feet ........................................................ 14
3.6 Connecting AC/DC Power ....................................................................................................................... 15
3.6.1 Connecting AC/DC Power Cable .......................................................................................................... 16
3.6.2 ENVIRONMENTAL CONDITIONS ............................................................................................................ 19
3.6.3 Using a SOLAR PANEL TO POWER SOLYS 2 ........................................................................................... 19
3.6.4 Enabling Power / Led STATUS .............................................................................................................. 20
3.6.5 Led STATUS ........................................................................................................................................ 20
3.7 Alignment of THE SOLYS 2 ...................................................................................................................... 22
3.8 Secure m8 bolts ...................................................................................................................................... 23
4 ACCESSORY INSTALLATION ..................................................................................................................... 24
4.1 Mounting Side Mounting Plate (For shading assembly or CHP 1 ............................................................... 24
4.2 Side Mounting Plate + Pmod-wrc pmo6 absolute cavity Pyrheliometer ..................................................... 25
4.3 Side Mounting Plate + Middleton SPO2 sun photometer .......................................................................... 26
4.4 Side Mounting Plate + Eppley (A)hf absolute cavity pyrheliometer ............................................................ 27
4.5 Attaching Pyrheliometer. ......................................................................................................................... 28
4.6 Mounting Sun sensor. ............................................................................................................................. 29
4.6.1 Alignment of Sun Sensor ..................................................................................................................... 32
4.7 Shading Ball Assembly .................................................................................................................... 33
4.8 Top Mounting plate assembly. ........................................................................................................ 37
4.9 Mounting Kipp radiometers without Ventilation unit. ...................................................................... 38
4.10 Mounting Kipp radiometers with Ventilation unit. ............................................................................ 39
4.11 Mounting Eppley radiometers with or without Ventilation unit. ........................................................ 40
4.12 Shading ball rods assembly. ............................................................................................................ 41
5 EXTRA ACCESSORIES. ..................................................................................................................... 43
5.1 Tilted Pyranometer mounting kit targeting the PV market. ...................................................................... 43
5.2 Small Top mounting plate for installing a single Kipp & Zonen radiometer. ............................................. 44
6 ETHERNET COMMUNICATION .......................................................................................................................... 45
6.1 EXTERNAL COMMANDS ........................................................................................................................... 49
6.2 Interfacing with thrid party applications .................................................................................................. 51
7 MAINTENANCE ............................................................................................................................................... 53
8 SOLVING PROBLEMS ........................................................................................................................................ 54
8.1 PROBLEM CHECK-LIST .............................................................................................................................. 54
8.2 FAQ ........................................................................................................................................................ 55
9 SOFTWARE OVERVIEW ..................................................................................................................................... 56
9.1 Algorithm ............................................................................................................................................... 56
10 FIRMWARE ...................................................................................................................................................... 57
10.1 Firmware upgrade ................................................................................................................................... 57
11 DRAWING SIDE MOUNTING PLATE ................................................................................................................... 59
12 DRAWING LARGE TOP MOUNTING PLATE ......................................................................................................... 60
13 HEIGHT SPECIFICATIONS SOLYS 2 INCLUDING INSTRUMENTS. .......................................................................... 61
14 PARTNUMBERS SHADING ASSEMBLY. ............................................................................................................... 62
15 HOW TO GUIDE THE CABLES ........................................................................................................................... 63
16 MOUNTING UVS INSTRUMENT ......................................................................................................................... 64
1 GENERAL INFORMATION
1.1 INTRODUCTION TO THE SOLYS 2
The SOLYS 2 two-axis sun tracker is an all-weather positioning platform used to point specialized
instruments at the sun’s movement across the sky. It is fully automatic and does not require a computer or
software for installation.
The integrated GPS receiver automatically configures location and time data. Multi-colour LEDs indicate the
operating status and an Ethernet port allows for software upgrades. The high-efficiency belt drive system
requires no maintenance.
The tough and distinctive cast aluminium housing has an integrated tripod stand with levelling feet. A side
plate with mountings for a Kipp & Zonen pyrheliometer is included as standard and a second side plate can
be fitted for an additional pyrheliometer. A top mounting plate is available for convenient mounting of up to
three Kipp & Zonen radiometers.
The shading assembly accessory includes the top mounting plate and allows the tracker to be configured as
a complete solar monitoring station.
SOLYS 2 does not suffer from internal clock drift because time is updated by the GPS receiver. A sun sensor
is optional available for active tracking where the stability of the support platform cannot be guaranteed.
SOLYS 2 has been designed to provide reliable, affordable sun tracking for small and medium sized
payloads. (<20Kg) Its accuracy is excellent for solar monitoring applications.
The built in power supply accepts both 24 VDC and 90 – 264 VAC and allows the DC Voltage to be used as a
backup.
SOLYS 2 is an all weather instrument providing optimal performance even in the harshest climates (from
equatorial to Polar region). The built in heater extends the operating temperature down to -40°C and
operates from AC power only. The SOLYS 2 features high accuracy, resolution and repeatability.
A standard SOLYS 2 with no accessories is shown in Figure 1.1.
Figure 1.1: SOLYS 2 standard delivery
1.2 MANUAL
The SOLYS 2 INSTRUCTION MANUAL is intended for customers who have purchased the SOLYS 2 with some
or all of the accessory items that can be used to enhance or expand its capabilities. It includes all the
information necessary to install and operate the SOLYS 2 for stand-alone operation.
2 SPECIFICATIONS OF THE SOLYS 2
SOLYS 2
Comments
Performance
Pointing accuracy
< 0.1 º
Meets BSRN requires requirements
Torque
20 Nm
Payload
20 kg
Balanced
Angular velocity
5 º/s
Angular acceleration
3.6 º/s²
Rotation
110 º zenith
540 º azimuth
Protection against over
rotation and damage
Physical limit stops
Operating Conditions and Dimensions
Supply voltage
18 to 30 VDC
(nominal 24 DC)
Allows for battery charging or under load
90 to 264 VAC,
50 / 60 Hz
For world-wide use
Power consumption
during Sun Cycle
20 W maximum
DC Power
120 W maximum
AC Power with heater operating
Power consumption after
Sun Cycle
13 W maximum
DC Power
113 W maximum
AC Power with heater operating
Storage temperature
- 40 to + 50 ºC
Operating temperature
range
- 20 to + 50 ºC
DC Power
- 40 to + 50 ºC
AC Power (heater standard)
Weight
23 kg
For standard tracker
5 kg
Tripod stand
Dimensions (WxDxH)
50 x 34 x 38 cm
(excluding tripod stand)
Includes standard pyrheliometer mounting
Bubble level accuracy
< 0.1°
Relative to zenith shaft
Compliance to international standards
Environmental protection
IP 65
Suitable for all-weather outdoor use
CE compliance
Yes
Materials
Suitable for coastal use and areas with pollution
Features
Transmission
Inverted tooth belts
Pre-tensioned, no adjustment needed
Connections
Plug and socket for
AC power, DC power,
Ethernet
GPS for location and time
/ date information
Standard
Antenna on top of housing
Pyrheliometer mounting
One side plate and
mounting kit as standard
For Kipp & Zonen CH 1 or CHP 1
Mounting base
Standard tripod
Includes adjustable feet for leveling
LED Indicators for
Power, internal
temperature and status
Multi-color to indicate various modes
Customer operation
Installation
Plug-and-play, no PC
GPS acquires location and time / date
required
Functional self test
Standard
Multi-color LED status indicator
Test / diagnostic facility
Standard
Via Ethernet port
Sun tracking mode
Standard
Michalsky algorithm (1988)
Firmware update possible
Flash memory
Via Ethernet port
Maintenance
No scheduled maintenance
required
Annual inspection recommended
Automatic restart after
power interruption
Yes
Options
Sun sensor kit
For active sun tracking
Plug in unit with alignment adjustment.
3.12° field of view
Second side mounting
plate
For fitting to zenith axis
shaft on opposite side to
standard Pyrheliometer
mounting
Does not include instrument mounting
brackets
Top mounting plate
3 positions for Kipp &
Zonen radiometers (with or
without CV 2 ventilation
units) or Eppley PSP / PIR
(with or without VEN
ventilation units)
No adaptors required
Shading ball assembly
Includes top mounting plate
and second side mounting
plate and 2 shading balls
on adjustable rods
Shading ball height adjustable to suit
radiometers above
Radiometer mounting kits
For Kipp & Zonen CH 1 or
CHP 1 Pyrheliometer
All require a side mounting plate
For PMOD-WRC PMO 6
absolute cavity
Pyrheliometer
For Middleton SP02 or
SP01-L sun photometer
For Eppley HF or AHF
absolute cavity
Pyrheliometer
Table 2.1: Operating specifications of the SOLYS 2
3 INSTALLATION
The following sections provide information on the installation of the SOLYS 2.
The installation consists of the following steps which will be explained step by step in the sub chapters:
3.1 Required tools for SOLYS 2 mounting
3.1.1 Required tools for Shading Ball Assembly / sun sensor
3.2 Minimum operating area / considerations
3.3 Create a firm base to mount the tripod stand with the K&Z logo pointing East
3.4 Mount the tracker on the tripod with the E on the mounting flange pointing East
3.5 Level the SOLYS 2 using the integrated bubble level and tripod feet
3.6 Connecting AC/DC Power
3.7 Alignment of the SOLYS 2
3.8 Fasten tripod feet to the firm base and check alignment.
4.1 Mounting second Side Mounting Plate (optional)
4.5 Attaching Pyrheliometer (optional)
4.6 Mounting Sun sensor (optional)
4.6.1 Alignment of Sun Sensor (optional)
4.7 Shading Ball Assembly (optional)
4.8 Top mounting plate assembly (optional)
4.9 Mounting Kipp radiometers without Ventilation unit (optional)
4.10 Mounting Kipp radiometers with Ventilation unit (optional)
4.11 Mounting Eppley radiometers with/without Ventilation unit (optional)
4.12 Shading ball rods assembly. (optional)
Apart from the creation of the tripod support base and the assembling of the accessories and instruments,
the levelling and the fine adjustment is only a matter of minutes. However a clear sun is required to do
this. It is important that these steps are carried out in this order.
SOLYS 2 has various accessories to enhance and expand its operation, including:
• Top Mounting Plate
• Extra Side Mounting Plate
• Pointing & Shading Ball Assembly:
Including one extra Side Mounting Plate and a Top Mounting Plate.
• Sun Sensor
• Mounting kits for various instruments for direct solar radiation measurement.
• Ventilation units for Pyranometers/Pyrgeometers
3.1 REQUIRED TOOLS FOR SOLYS 2 MOUNTING
For installation on site the following materials are supplied with the SOLYS 2
Allen Wrench key type 6 (for M8 bolts for tripod)
Allen Wrench key type 3
Allen Wrench key type 2.5
Screws M8 x 20 plus M8 washers
Required but not supplied are:
Screwdriver for connection of power cable to the connector
Cable for power connection of the SOLYS 2
Compass to find geographical East.
3.1.1 REQUIRED TOOLS FOR SHADING BALL ASSEMBLY / SUN SENSOR
The tools required for the mounting of the shading ball assembly are supplied with this option.
Required but not supplied are:
A Ruler, to measure the position of the optional sun sensor.
3.2 MINIMUM OPERATING AREA / CONSIDERATIONS
SOLYS 2, complete with all the accessories attached, requires a substantial amount of unobstructed area to
operate properly. This should be kept in mind when deciding where and how the unit is going to be
installed. Figure 4.1 shows the minimum operating area with respect to both the Azimuth and Zenith axis of
a SOLYS 2 complete with all accessories including Tripod Stand and Shading Ball Assembly.
Note:
Keep in mind that the angle of Azimuth (horizontal) rotation changes during the year.
A SOLYS 2 installed in the winter will rotate further during summer, so make sure no objects will block its
movement. To prevent blocking from its movement a rotation lap is performed by the tracker at initial power
up. (270° to the left and 270° to the right starting from home position)
Figure 4.1: Minimum Operating Area (with Shading Assembly)
Important:
It is important to consider the following points before/during the installation of a SOLYS 2.
• Verify that all cabling is routed properly to prevent cables from catching on any fasteners
supports,he SOLYS 2 or instruments.
• Ensure that the surface on which the Suntracker will be mounted is reasonably level, but above all it
is very important to create a very firm base for the feet of the Tripod stand to sit upon.
• Make sure that the site will be free from any obstructions within the operating circle and that there
is a clear view to the horizon in all directions.
• Make sure that the SOLYS 2 and accessories will be accessible for maintenance purposes.
• Make sure that the SOLYS 2 is located in such a way that shadows will not be cast onto the
radiometers at any time.
• Ensure that before operation of the SOLYS 2 the Sun Sensor cable and other mounted instrument
cabling will not catch on any fasteners or supports. During the inital power up a rotation lap will be
performed to check for blockage or cables which are too short..
3.3 CREATE A FIRM BASE TO MOUNT THE TRIPOD STAND WITH THE
KIPP & ZONEN LOGO POINTING EAST
The tripod feet have 11 mm mounting holes to fix the SOLYS 2 to a firm base. Illustration 4.4 will provide
the necessary information to create a firm base.
NOTE: The tripod feet has a KIPP & Zonen logo present which needs to be pointed to the
East !
It is advised to perform the leveling and alignment during installation of the SOLYS 2, options and
instruments first, before actually tighten the tripod feet to the firm base.
Figure 4.4: Tripod Stand footprint
3.4 MOUNT THE TRACKER ON THE TRIPOD WITH THE E ON THE MOUNTING
FLANGE POINTING EAST
The SOLYS 2 is supplied with a standard ∅ 102 mm bottom flange, which has a 3-hole M8 mounting pattern
to match the Tripod Stand with leveling feet. The tripod has 3 slots for mounting the 3 M8 bolts to the
bottom flange. Both the E mark on the bottom flange and the K&Z logo on the tripod must point East when
the SOLYS 2 is mounted. Ideally the bolts should be in the middle of the slots when the tripod is mounted to
the SOLYS 2. This allows fine tuning the position afterwards
Note: Turn in the M 8 bolts by hand but do not fasten during first installation. Only after the alignment with
the sighting target on the pyrheliometer (bracket) they need to be fastened. (chapter 3.7)
Remember that sun is required for this alignment.
Figure 4.2: Mounting the SOLYS 2 on the Tripod Stand
Figure 4.3: SOLYS 2 Bottom Flange Dimensions.
Note: When different mounting bolts are used they must not protrude through the bottom flange
Tip: When installed an initial Azimuth orientation due East with the help of a compass will do. When
the SOLYS 2 is powered later on, exact positioning can be performed, when sun is available.
3.5 LEVEL THE SOLYS 2 USING THE INTEGRATED BUBBLE LEVEL AND TRIPOD FEET
Prior to activating the SOLYS 2, it must be levelled on its mounting surface. To help accomplish this
task, the SOLYS 2 is equipped with a high accuracy bubble on top of the housing. Adjust the levelling
feet on the tripod stand to move the bubble into the centre of the level. The levelling feet can be easily
adjusted using a 13 mm wrench. The accuracy of the SOLYS 2 is within 0.1°when the bubble is within
the circle.
We recommend during installation to keep the bubble inside the ring for both the SOLYS 2 and the
Pyranometers.
If however the bubble is half out of the ring, the instruments (Pyranometer and SOLYS 2) are still within
0.1 ° (BSRN requirement)
3.6 CONNECTING AC/DC POWER
CAUTION, RISK OF ELECTRIC SHOCK, ALWAYS CONNECT A PROTECTED EARTH
Important: Power supply
SOLYS 2 can be operated on either 115/230 VAC or 24 VDC. In case both the AC and DC supplies are
present and the AC power is within its operating range (90 – 264 VAC) the SOLYS 2 will use the AC power. If
the AC power fails and DC power is present the SOLYS 2 will without interruption continue on DC power.
Inside the SOLYS 2 a 4 A slow blow fuse is used for the internal heater.
Important: Operating Temperature
SOLYS 2 has an operating temperature range of -20°C to +50°C when operating on 24 VDC. When AC power
is applied the standard built-in heater will be used. The use of the heater extends the operating temperature
to - 40°C. The internal heater automatically switches on below 5ºC. If the SOLYS 2 is first started below -20°C
it can take up to 30 minutes before the interior is above - 20°C and the SOLYS 2 will start.
Table 4: SOLYS 2 Operating Temperature Range.
SOLYS 2 operating on DC power (heater not functional)
-20°C to +50°C
SOLYS 2 operating on AC power (heater operational)
-40°C to +50°C
Figure 3.1: connectors on the underside of the SOLYS 2
3.6.1 CONNECTING AC/DC POWER CABLE
This section will explain how to make and connect your power cable to power the SOLYS2.
Important Rotation lap
Please understand that by applying power to the SOLYS 2 it will trigger a routine initialization
procedure.
During this procedure it will check for GPS signal, make a 540° rotation and stops in home position for
a complete minute.
Therefore it’s advisable to actually apply the power while checking chapter 3.6.4
SOLYS 2 is supplied with 2 waterproof power connectors, for both AC and DC. These connectors are in
accordance with safety regulations for outdoor usage. The voltage drop over the cable should not cause the
supplied voltage to be out of specifications.
Both the AC and DC connector are suitable for cable diameters between 6 and 12 mm. For 6 – 9 mm
and 9 – 12 mm different sealing rings are used.
The AC connector is female type Hirschmann CA 3 LD connector.
The DC connector is a male type Hirschmann CA 3 LS connector.
Illustration 3.2 indicates the pin numbers, where pin three is NOT used
Figure 3.2: pin numbering in male and female power connectors
For AC power:
Pin 1: L1
Pin 2: N
Pin Earth = Protected Earth
For DC power:
Pin 1: +24Vdc
Pin 2: GND
Pin Earth = Protected Earth
Drawings for both connectors and pin numbers including types of cable are given in fig 3.4 and fig.
3.5.
The pin numbers and ground connection for the individual wires are visible inside the connector. The
ground connection is raised slightly above the other connections.
21 mm 5 mm
Power cable for outdoor use (not included)
Outer diameter: 6 - 12 mm
No. of conductors: 3
Conductor colors: Blue, Brown, Green/Yellow
Female connector (included)
Hirschmann: CA 3 LD
Cable connections:
1 = Brown (L)
2 = Blue (N)
= Green/Yellow (Protective Earth)
9 - 12 mm
6 - 9 mm
Power cable for outdoor use (not included)
Outer diameter: 6 - 12 mm
No. of conductors: 3
Flexible wires:
Conductor colors: Red, Brown, Green/Yellow
Figure 3.4: Power Cable Connector for 90 – 264 VAC
21 mm 5 mm
9 - 12 mm
6 - 9 mm
Male connector (included)
Hirschmann: CA 3 LS
Cable connections:
1 = Red (+ 24 VDC)
2 = Black (24 VDC GND)
= Green/Yellow (Protective Earth)
Power cable for outdoor use (not included)
Outer diameter: 6 - 12 mm
No. of conductors: 3
Flexible wires:
Conductor colors: Red, Brown, Green/Yellow
Figure 3.5: Power Cable Connector for 24 VDC
3.6.2 ENVIRONMENTAL CONDITIONS
Important: SOLYS 2 rear cover
SOLYS 2 does not contain any user serviceable parts inside. Therefore it is advised not to open the rear
cover. Doing so can defeat the internal optical sensors which may result in physical damage to the SOLYS 2
and/or any attached equipment. Such damage is not covered under warranty.
Important: Precipitation
With the SOLYS 2 rear cover installed properly such that all 8 screws are secured, the SOLYS 2 is
environmentally protected to IP65, according EN 60529: 1991 + CI 1993. This qualifies the SOLYS 2 to be
used in weather conditions with all types of precipitation.
Important: Circuit breaker
A power on/off switch is not a part of the SOLYS 2; requirements for electrical equipment installed outdoors
specify that:
• A power isolator (switch or circuit-breaker) must be included in the cable installation.
• The isolator (switch or circuit-breaker) must be in close proximity to the equipment and within easy
reach of the operator.
• The isolator (switch or circuit-breaker) must be marked as the power disconnection device for the
equipment.
used in weather conditions with all types of precipitation.
3.6.3 USING A SOLAR PANEL TO POWER SOLYS 2
If the system is operating on solar power only, please be aware of the reduced number of hours of sunlight
during the winter
On cloudy days less than 50% of the normal radiation comes in
Rule of thumb is to use 10 times as much solar panel power.
How to determine what kind of solar panel is required; Please add the power consumption of each additional
instrument, PC`s, data logger or any other device together with the power consumption of the SOLYS2 and
multiply this by 10.
Power consumption SOLYS 2 on DC : 20W during sun cycle.
After the sun cycle, the SOLYS 2 will start its energy savings program and put itself to sleep mode.
During this sleep mode the power consumption is 13W.
20 minutes before the sun rises, the SOLYS 2 will wake up, go to its home position and starts its active
tracking mode with full power consumption.
If no other power is available, also a few days without sun should be covered by the back-up battery.
If the backup batteries are 2x12 V, they can be used in series for the SOLYS 2 (24 V)
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