aerl CoolMax SRX-R Series User manual

CoolMax SRX-R
Charge Controller
Installation and Operation Manual
Models
SRX-R 450/55-48
SRX-R 600/70-48

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
2
AER09-R REV 1.0.0
About AERL
Australian Energy Research Laboratories (AERL) was founded by Stuart Watkinson (BE Elec. Eng., Grad. M.I.E.A) in
1985 to commercialize the “Power Optimizer”, a revolutionary solution to a complex problem, developed while studying at
the University of Queensland in Brisbane, Australia.
Unlike many inventors, Stuart possessed not only a great idea but also the entrepreneurial skill to turn it into a
commercially viable product. The “Power Optimizer” would eventually come to be known as the AERL MAXIMIZER™, the
world’s first truly Universal Maximum Power Point Tracker (MPPT).
Today, AERL manufactures a range of h i g h l y r e l i able and efficient specialized power electronic controllers for use in Solar,
Micro Hydro, Micro Wind, and Cathodic Protection applications.
Contact Information
Address: 2/75 Bluestone Circuit,
Seventeen Mile Rocks, 4073,
Queensland, Australia
Phone: [phone]
Email: [email protected]
Website: https://www.aerl.com.au
Disclaimer
UNLESS SPECIFICALLY AGREED TO IN WRITING, AUSTRALIAN ENERGY RESEARCH LABORATORIES:
(a) MAKES NO WARRANTY AS TO THE ACCURACY, SUFFICIENCY OR SUITABILITY OF ANY TECHNICAL OR
OTHER INFORMATION PROVIDED IN ITS MANUALS OR OTHER DOCUMENTATION.
(b) ASSUMES NO RESPONSIBILITY OR LIABILITY FOR LOSS OR DAMAGE, WHETHER DIRECT, INDIRECT,
CONSEQUENTIAL, OR INCIDENTAL, WHICH MIGHT ARISE OUT OF THE USE OF SUCH INFORMATION.
THE USE OF ANY SUCH INFORMATION WILL BE ENTIRELY AT THE USER’S RISK.
Notice of Copyright
CoolMax SRX-R Charge Controller User Manual © 2023 by AERL Pty. Ltd. All Rights Reserved.
Trademark
AERL and the AERL Logo are trademarks owned by AERL Holdings Pty. Ltd. and used by AERL Pty. Ltd under license.
These trademarks may be registered in Australia and other countries.
Effective Date
May 2023 (5/2023)

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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AER09-R REV 1.0.0
Table of Contents
Warranty Conditions .......................................................................................................................................... 5
Specifications ..................................................................................................................................................... 6
Introduction ......................................................................................................................................................... 7
Features ......................................................................................................................................................... 7
Firmware ........................................................................................................................................................ 7
Installation ........................................................................................................................................................... 8
Standards & Requirements .......................................................................................................................... 8
Grounding ..................................................................................................................................................... 8
Mounting the Shelf ....................................................................................................................................... 9
Wiring Information ...................................................................................................................................... 10
Wire and Disconnect Sizing ................................................................................................................. 10
CoolMax SRX-R 450/55-48 ............................................................................................................................. 10
CoolMax SRX-R 600/70-48 ............................................................................................................................. 10
Backplane Terminations ...................................................................................................................... 11
Operation ........................................................................................................................................................... 12
Start-Up & Shutdown Procedure ............................................................................................................... 12
Programming the Device ........................................................................................................................... 12
Device Status Indicator .............................................................................................................................. 13
Battery Charge Profile ................................................................................................................................ 14
Charge Profile Configuration ............................................................................................................... 15
Setting the Battery Charge Profile with AERL Link ........................................................................... 16
Ground Fault Detection .............................................................................................................................. 18
Ground Fault Sensitivity ............................................................................................................................ 19
Communications Protocols ....................................................................................................................... 20
Troubleshooting – Error Codes ...................................................................................................................... 21

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Important Safety Information
This Installation Manual contains important safety information and installation instructions for the
AERL COOLMAX SRX-R MPPT Solar Charge Controller.
The following symbols are used throughout this user manual to indicate ideal installation methods,
potentially dangerous conditions, and important operational information.
• This User Manual provides detailed installation and usage instructions for the COOLMAX SRX-R unit. It is
recommended that all the Instructions and Cautions in this User Manual be read before beginning
installation.
• Only qualified electricians and technicians should install the COOLMAX SRX-R. This manual is intended
for all installation technicians and the system owner.
• Do not disassemble or attempt to repair the COOLMAX SRX-R unless you are a qualified technician and
have authority in writing from AERL to do so.
• AERL will not be held responsible in any way for the mishandling of this product or for installation of the
product in a manner that does not follow the instructions in this manual or as advised by an AERL
technician.
IMPORTANT
Indicates information that must be followed to ensure proper operation of the
COOLMAX SRX-R.
Indicates a critical procedure for the safe installation of the COOLMAX SRX-R. Use
extreme caution when performing this task.
CAUTION
About this Manual
IMPORTANT

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
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Note: Warranty conditions remain current until the next revision of this document is published. Proof of purchase is required when
making a warranty claim.
1 Warranty Duration from the Date of Purchase
Warranty Requirements
Total Warranty Duration
1. You are the original purchaser of the CoolMax SRX-R.
5 Years
Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a
replacement or refund for a major failure and compensation for any other reasonably foreseeable loss or damage. You are
also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not
amount to a major failure.
AERL will bear the cost of parts and labour to repair any manufacturing faults found within the terms and period of this
warranty and pay the cost of freight to return the repaired CoolMax SRX-R controller within Australia/New Zealand but the
method of freight will be determined by AERL.
An allowance is made for the labour required to disconnect or reinstall faulty parts up to the value of $220 AUD excluding
GST.
All installation and user conditions as set down in the instruction manual must be strictly adhered to as failure to do so
may void your warranty. Any faults or like faults caused by lightning, water or moisture ingress, vermin infestation,
improper voltage, faulty installation, use of the product in a manner for which it is not intended, alterations which affect the
reliability or performance of the unit but are not attributable to faulty manufacture, or damage caused by other system
components will not be covered under warranty.
In the event of the product being out of service, AERL shall bear no responsibility for any consequential loss or expense.
AERL will not be held responsible for any misleading or incorrect information conveyed by anyone not directly employed
by AERL.
For claims under warranty, the faulty product(s) must be returned to AERL’s facility at 2/75 Bluestone Circuit, Seventeen
Mile Rocks, 4073, QLD, Australia after contacting AERL and receiving the appropriate RMA documentation from AERL.
Warranty Conditions

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
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Characteristics
SRX 450/55-48
SRX 600/70-48
Nominal Battery Voltage / Vdc Range
24 V | 48 V / 20 - 60
24 V | 48 V / 20 - 60
Max Charge Current
55 A
70A
Nominal Charge Power
1584 W @ 24 V
3168 W @ 48 V
2016 W @ 24 V
4032 W @ 48 V
Max PV Input Power
Nominal Charge Power x 1.33
Nominal Charge Power x 1.33
Max PV Input Voltage (Voc)
450 V
600 V
MPP Voltage Range (Vmp)
100 – 360 V
170 – 500 V
Min PV Operating Voltage
100 V
100 V
Max PV Input Current (Imp)
14 A
14 A
Max PV Short Circuit Current (Isc)
20 A
20 A
Device Startup Voltage
60 V
60 V
Total Backfeed Current (Ibf Total)
0 A
0 A
Overload Behaviour
Power Limitation
Power Limitation
PV Reverse Polarity Protection
Yes
Yes
Earth Leakage Current Detection
Yes
Yes
Overvoltage Category
DC II
DC II
Overvoltage Protection
DC Type II
DC Type II
Safety Protection Class
I
I
Pollution Degree (Int & Ext)
II
II
Max Altitude Rating
2000m
2000m
Max Conversion Efficiency
96%
96%
Ambient Operating Temperate Range
(Maximum Charge Current derates by
up to 10% Per ° C above 80% Ambient
° C)
-20 to +50 °C
-20 to +50 °C
Storage Temperature
-30 to +70 °C
-30 to +70 °C
Self-Consumption @ Idle
3.5 W
3.5 W
Allowable Relative Humidity
4 – 95% (Non-Condensing)
4 – 95% (Non-Condensing)
Cooling Method
Active (User Serviceable)
Active (User Serviceable)
Required Cabinet Air Exchange Rate
(Intake @ 40°C)
25 m3/hour
25 m3/hour
Communications
RS485 / CAN Bus
RS485 / CAN Bus
Certifications
IEC62109-1:2010
EN61000.6.3:2012
EN61000.6.4:2012
IEC62109-1:2010
EN61000.6.3:2012
EN61000.6.4:2012
General Specifications
Parameter
Typical
Weight
4 kg
Dimensions (H x W x D)
432 x 192 x 78 mm
Enclosure Type
Indoor Type 1 / IP20
Input / Output Power Connectors
Backplane Connector
Specifications

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Thank-you for purchasing an Australian made CoolMax SRX-R Series Charge Controller.
CoolMax Charge Controllers offer an efficient and reliable charging process that not only maintains battery
efficiency and life but maximizes power generation by utilizing the full potential of your PV array.
Features
CoolMax Charge Controllers utilize an advanced form of Maximum Power Point Tracking (MPPT)
technology to extract the maximum power available from your PV array, efficiently charging your batteries
and maximizing power generation.
AERL’s Maximum Power Point Tracking (MPPT) algorithm has been proven to be highly robust, resistant to
local extremes, and results in power losses of less than 0.5% over the whole operating temperature range
of a PV Array.
• High Input Voltage for Ease of Install
• On-Board Ground Fault Detection
• PV Array Oversizing Support (+33%)
• Superior Peak Power Efficiency
• Built-In Overload and Thermal Protection
• Reverse Polarity and Current Protection
• Designed for Long Term Reliability
• Australian Made
Firmware
This user manual covers CoolMax SRX-R Control Firmware Revisions v1.7 and above.
Introduction

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Standards & Requirements
All installations must comply with national and local electrical standards and codes of practice, and the
CoolMax SRX-R must be installed in a clean, dry location away from direct sunlight. AERL always
recommends professional installation. No on-going maintenance is required.
Grounding
CoolMax Charge Controllers are designed to be installed in floating systems but contain provisions for positive
functional earthing for telecom applications if required.
Installation
IMPORTANT
CAUTION – Equipment Damage
The SOLAR DC ISOLATOR/BREAKER at the input side must be in the OFF position before
connecting or disconnecting the MPPT Charge Controller.
CoolMax Charge Controllers are not designed to be used in parallel with other Third-
Party Charge Controllers and this will void your warranty.
IMPORTANT
The Chassis Ground (located inside the enclosure) is marked with the following symbol:
CAUTION – Hazard
If damaged or malfunctioning, the AERL controller should only be disassembled and
repaired by a qualified service centre. Please contact your local authorized distributor for
assistance.
Incorrect reassembly risks malfunction, electric shock, or fire.
DO NOT FUNCTIONALLY EARTH THE ARRAY if a negative earth is used for the batteries, load, or DC
system.
CAUTION – Hazard

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
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Mounting the Shelf
The SRX-R shelf must be mounted horizontally in a suitably ventilated lockable cabinet ensuring the backplane area is
restricted to licensed electricians and qualified technicians.
Figure 1: SRX-R Modules in Shelf

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Wiring Information
This section will provide information and instructions for safely wiring up the DC connections on the CoolMax
SRX-R.
Wire and Disconnect Sizing
Use a minimum of #6 AWG (16 mm2) wire for the output between the backplane and the battery bus bar or
termination and use an appropriately sized insulated crimp ferrule when terminating both the input and
output connections.
Tor q ue a l l Co ol M ax w i r e a nd g r ou nd t e rm i n a ls t o 1.7 Nm (15 in-lb).
CoolMax SRX-R 450/55-48
• The output current limit of the CoolMax SRX-R 450/55-48 is 55 amps.
• Use a 63A Non-Polarized DC Circuit Breaker between the controller output and load.
o Recommended Option: Beny BB1-63 63A 600V 2-Pole Circuit Breaker
CoolMax SRX-R 600/70-48
• The output current limit of the CoolMax SRX-R 600/70-48 is 70 amps.
• Use a 125A Non-Polarized DC Circuit Breaker between the controller output and load.
o Recommended Option: Beny BD-125 125A 1000V 4-Pole Circuit Breaker
Please refer to the relevant IEC or AS/NZS electrical code for recommendations on PV array cable sizing,
length, and ampacity.
All devices connected to the controller must have suitable insulation in accordance with the relevant product
standards.
IMPORTANT
• Wire sizes must comply with local and national standards. Input conductors and
circuit breakers must be rated at 1.56 times the short-circuit current of the PV array.
• Copper wiring must be rated at 75°C or higher.

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Figure 2: SRX-R Backplane
CAUTION – Equipment Damage
Reversing the polarity of the output may damage the CoolMax SRX-R and void product
warranty.
Confirm polarity with a multi-meter prior to closing the input and output circuit breakers.
Backplane Terminations
PV Terminal (1)
Battery Terminal (1)
USB-B
Programming
Port
COMMS
RJ45 x 2
(IN/OUT)
USB
Change Over
Switch
PV Terminal (2)
Battery Terminal (2)

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
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Start-Up & Shutdown Procedure
The CoolMax SRX-R will start-up when a voltage above 60Vdc is applied to the PV Input – The device will not
power up from the Battery terminal.
To s t a rt t h e de vi c e, c o n n ec t t h e Battery first, and then turn the PV Isolator/Breaker on. The LED will flash blue
for approximately 60 seconds, and then begin to charge – USB setup will be required on first start-up.
To shut down the device, turn the PV Isolator off, wait for the LED to turn off, and then disconnect the battery
breaker to isolate the controller.
Programming the Device
When the CoolMax SRX-R is first powered on,
the device will run a self-test and then the LED
indication strip will flash yellow to indicate
no charge profile has been configured.
The CoolMax SRX-R is programmed via the
USB-B port located on the backplane board
as demonstrated in Figure 4 to the right.
Note - The USB Selection Switch must be
toggled between MPPT 1 and MPPT 2.
The AERL Link Software for Windows 10/11
can be downloaded at the URL below.
Instructions for setting the charge profile
located on Page 16.
Operation
Figure 3: USB-B Programming Port and Toggle
Switch
CAUTION – Equipment Damage
Do not remove an SRX-R MPPT from the backplane while charging – Turn off
the PV isolator first to prevent equipment damage.
link.aerl.com.au

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Device Status Indicator
Green
OK
Blue
START-UP / SLEEP
Yel lo w
CHARGER DISABLED / SETUP REQUIRED
Red
FAULT
Figure 4: LED Indication States

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
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Battery Charge Profile
The CoolMax SRX-R charge output will not automatically activate for safety reasons. Prior to activating the
charge output, the charge profile must be configured for the relevant battery solution being utilized.
The SRX-R operates using an advanced three-stage charging process and has pre-set charge voltage profiles
for each supported nominal battery voltage. That said, AERL always recommends referring to the battery
manufacturers specifications regarding charge voltages for optimal battery life and performance.
These voltages can be adjusted in the charge profile settings. Refer to Page 16 for instructions.
Figure 5: Battery Charge Profile Illustrated
IMPORTANT
The CoolMax SRX-R default charge profile is intended for a generic LiFePo4 battery solution.
AERL supports most other battery chemistries that do not require external BMS communications.
AERL is working with various battery manufacturers to expand out-of-the-box comms support for
Lithium batteries that require communication with the Charge Controller.
Please contact AERL support to confirm compatibility prior to installation. Additional battery
support will be rolled out via Over-The-Air firmware updates.
Battery Voltage
Time
Absorb
Time
Absorb Voltage
Float Voltage
Rebulk Voltage
Falls Off Float
New Charge Cycle

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Charge Profile Configuration
The CoolMax SRX-R allows for extensive flexibility when it comes to charge profile parameters to suit
numerous different modern battery chemistries and manufacturers requirements.
Our programmable charge profile allows for the configuration of the Battery Charge Rate, and the Absorb,
Float, Re-Bulk, and Equalization voltage points.
The default charge profile is suitable for most applications but to determine the optimal charge profile for your
application, please refer to your battery manufacturer’s user manual or datasheet.
The CoolMax SRX-R Default Charge Profiles are as follows:
SRX-R 450/55-48
SRX-R 600/70-48
Nominal Battery voltage
48 V
48 V
Max Charge current
55 A
70 A
Absorption voltage
57.6 V
57.6 V
Absorption time
2 Hours
2 Hours
Float Voltage
55.2 V
55.2 V
Re-Bulk Voltage
52 V
52 V
IMPORTANT
An Equalization is only normally required for Flooded Lead-Acid cells that experience
sulfation because of poor charging practices over the lifetime of said cell.
Equalization is not required, nor recommended for LiFePo4 or other lithium-based
battery solutions and will likely cause damage unless otherwise advised by the
battery manufacturer.

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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Setting the Battery Charge Profile with AERL Link
Connect to the USB-B Port on the backplane, ensuring the USB Change-Over Switch (refer to Figure 2 on
Page 11) is set to the device you wish to program. Within a few seconds, the device will appear in the available
local devices list in AERL Link.
Click on the Device, select the Settings button on the device page to access the battery charging settings.
Charge settings are changed by clicking on the setting value and using the plus/minus arrows or the keyboard
to enter a new value.

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
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Once the required settings have been set, slide the charger enabled toggle to the right, and apply the
changes to the CoolMax SRX-R by clicking on the Apply button to begin charging.

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
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Ground Fault Detection
The CoolMax SRX-R features industry-first onboard PV and Battery system ground fault detection, with all connected
electrical poles checked for insulation degradation during the device’s start-up routine.
The device chassis must be connected to the same earth as the PV array for the ground fault detection to function. The
chassis earth point is located inside the access cover and indicated with the symbol demonstrated below.
Figure 10: Chassis Earth Point
IMPORTANT
The system earth configuration (Ground Fault Mode) must be adjusted in the AERL Link
software for use with functionally earthed systems otherwise an earth fault will be
detected on the earthed pole.

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
9th May 2023
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AER09-R REV 1.0.0
Ground Fault Sensitivity
The SRX-R ground fault detection offers three levels of sensitivity, all of which are compliant with the Australian PV
installation standards.
Low
100kΩ
Medium
50kΩ
High
30kΩ
The sensitivity of the ground fault detection can be configured in AERL Link as demonstrated in Figure 11 below.
Figure 11: Ground Fault Sensitivity Adjustment

USER MANUAL
COOLMAX SRX-R – Rack Mount
Australian Energy Research Labs
AER09-R – Rev 1.0.0
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Communications Protocols
The CoolMax SRX-R features both Controller Area Network (CAN bus) and ModBus RTU (RS485) compatible protocols
for remote monitoring and control functionality. The relevant protocol registry maps for integration are available from AERL
on request.
Both networking protocols can be accessed via the RJ45 connectors located inside the access cover.
The pin-outs for these connections are demonstrated in Figure 12 below.
Pin
Comms Connector
4
CAN High
7
CAN Low
5
RS485 A
6
RS485 B
8
GND
Figure 12: Comms Connector Pin-Outs