Epever Tracer 4215BN User manual

MPPT Solar Charge Controller
User Manual
Model：
Tracer4215BN

Contents
Important Safety Instructions 1
1 General Information 2
1.1 Overview 2
1.2 Characteristics 4
1.3 Maximum Power Point Tracking Technology 5
1.4 Battery Charging Stage 7
2 Installation Instructions 11
2.1 General Installation Notes 11
2.2 PV Array Requirements 12
2.3 Wire Size 12
2.4 Mounting 13
3 Operation 16
3.1 LED Indication 16
3.2 Setting Operation 17
3.3 Battery Parameters 18
3.4 Load Set Mode 22

4 Others 24
4.1 Protection 24
4.2 Troubleshooting 26
4.3 Maintenance 27
5 Technical Specifications 29
Annex I Conversion Efficiency Curve 31
Annex II Dimensions 32

1
Important Safety Instructions
Please reserve this manual for future review. This manual contains all safety,
installation, and operation instructions for the Maximum Power Point Tracking
(MPPT) controller in the Tracer BN series ("the controller" is referred to in this
manual).
General Safety Information
Read all the instructions and warnings carefully in the manual before
installation.
No user-serviceable component exists inside the controller. DO NOT
disassemble or attempt to repair the controller.
Mount the controller indoors. Prevent exposure to the elements and do not
allow water to enter the controller.
Install the controller in well-ventilated places. The controller's heat sink may
become very hot during operation.
Install appropriate external fast-acting fuses/breakers.
Disconnect all PV array connections and fast-acting fuses/breakers close to the
battery before controller installation and adjustment.
Power connections must remain tight to avoid excessive heating from a loose
connection.
WARNING
Do not install the controller in humid, salt spray, corrosion,
greasy, flammable, explosive, dust accumulative, or other severe
environments.

2
1 General Information
1.1 Overview
Appreciate you for choosing MPPT solar charge controller, the Tracer BN series.
Based on a common negative design and advanced MPPT control algorithm, with a
die-cast aluminum design for heat dissipation, products in this series are artistic,
economical, and practical.
With the MPPT control algorithm, products of this series can fast and accurately
track the photovoltaic array's best maximum power point (MPP). Obtain the
maximum solar energy in time, which remarkably improves energy efficiency. With
the Modbus communication interface, it is convenient for customers to expand
applications and monitor various fields. Such as telecommunication base stations,
household systems, caravan systems, street lighting systems, wilderness monitoring
systems, etc.
All-round electronic fault self-test and enhanced electronic protection functions could
prevent damage to system components from installation errors or system failures.
Feature:
Advanced Maximum Power Point Tracking (MPPT) technology, with no less
than 99.5% efficiency.
High-quality components, perfecting system performance, with a maximum
conversion efficiency of 98%.
Ultra-fast tracking speed and guaranteed tracking efficiency.
Accurately recognizing and tracking of multiple power points.
Reliable automatic limit function of maximum PV input power, ensuring no
overload.
Wide MPP operating voltage range.

3
Die-cast aluminum design, ensuring excellent heat dissipation characteristics.
12/24VDC automatically voltage-identifying system or user-defined working
voltage.
LED indicators showing system status, simple and clear.
Multiple load control modes: manual control, light ON/OFF, light On+Timer, and
time control.
Support multiple battery types, including lithium batteries
Battery temperature compensation function.
Real-time energy statistics function.
The RS485 communication bus interface and Modbus communication protocol
allow it to meet various communication requirements in different situations.
Available for PC monitoring and external display unit connecting like MT50 and
so on, realizing real-time data checking and parameter setting.

4
1.2 Characteristics
Figure 1-1 Tracer BN Series Characteristics
Item
Name
Item
Name
①
Heat Sink
⑥
Load Terminal
②
Charging LED indicator
⑦
RS485 Port
(Isolated RJ45 port)
③
RTS①Port
⑧
Button
④
Solar Terminal
⑨
Battery LED indicator
⑤
Battery Terminal
Explanation:
①Connect an RTS (Remote Temperature Sensor) to detect battery temperature
remotely.
⑤
⑥
⑨
⑦
⑧
④
①
②
③

5
1.3 Maximum Power Point Tracking Technology
Due to the nonlinear characteristics of the solar array, there is a maximum energy
output point (Max Power Point) on its curve. Traditional controllers, adopting the
switch charging technology and PWM charging technology, can't charge the battery
at the maximum power point. They can't harvest the maximum energy available from
the PV array. In comparison, the solar charge controller with Maximum Power Point
Tracking (MPPT) Technology can lock on the point to harvest the maximum energy
and deliver it to the battery.
The MPPT algorithm of our company continuously compares and adjusts the
operating points to locate the array's maximum power point. The tracking process is
fully automatic and does not need user adjustment.
As shown in Figures 1-2, the curve is the characteristic curve of the array. The
MPPT technology will boost the battery charge current by tracking the MPP.
Assuming the conversion efficiency of the solar system is 100%, the following
formula is established:
Normally, the VMpp is always higher than VBat. Due to the principle of energy
conservation, the IBat is always higher than IPV. The greater the discrepancy between
VMpp & VBat, the greater the discrepancy between IPV& IBat. The greater the
discrepancy between the PV array and battery, the bigger the reduction of the
system's conversion efficiency. Thus the controller's conversion efficiency is
particularly important in the PV system.
Figure 1-2 is the maximum power point curve, and the shaded area is the charging
range of a traditional solar charge controller (PWM Charging Mode). It can diagnose

6
that the MPPT mode can improve the usage of solar energy resources. According to
our test, the MPPT controller can raise 20%-30% efficiency compared to the PWM
controller. (Value may fluctuate due to the ambient circumstance's influence and
energy loss.)
Figure 1-2 Maximum Power Point Curve
The panel may appear Multi-MPP as shading from clouds, trees, or snow in actual
application. However, there is only one real Maximum Power Point. As Figure 1-3
show:
Figure 1-3 Mutil-MPP Curve

7
If the program works improperly after appearing Multi-MPP, the system will not work
on the real max. power point. It may waste most solar energy resources and affect
the system's normal operation. The typical MPPT algorithm, designed by our
company, can track the real MPP quickly and accurately, improve the array's
utilization rate and avoid wasting resources.
1.4 Battery Charging Stage
The controller has a three-stage battery charging algorithm (Bulk Charging,
Constant Charging, and Float Charging) for rapid, efficient, and safe battery
charging.
Figure 1-4 Battery changing stage Curve
A) Bulk Charging
In this stage, the battery voltage has not yet reached constant voltage (Equalize or
Boost Voltage). The controller operates in constant current mode, delivering its
maximum current to the batteries (MPPT Charging).

8
B) Constant Charging
When the battery voltage reaches the constant voltage set point, the controller will
start to operate in constant charging mode. This process is no longer MPPT
charging. In the meantime, the charging current will drop gradually. The process is
not the MPPT charging. Constant charging has two stages, equalize and boost.
These two stages are not carried out constantly in a full charge process to avoid too
much gas precipitation or overheating of the battery.
Boost Charging
The Boost stage maintains 2 hours in default. Users can adjust the constant time
and preset value of boost voltage according to demand.
The stage is used to prevent heating and excessive battery gassing.
Equalize Charging
WARNING
Explosive Risk!
Equalizing flooded batteries would produce explosive gases, so
well ventilation of the battery box is recommended.
CAUTION
Equipment damage!
Equalization may increase battery voltage to the level that
damages sensitive DC loads. Verify that all load allowable
input voltages are 11%greater than the equalizing charging set
point voltage.
Over-charging and excessive gas precipitation may damage
the battery plates and activate material shedding on them. Too
high an equalizing charge or for too long may cause damage.
Please carefully review the specific requirements of the battery
used in the system.
Some batteries benefit from equalizing charge regularly, which can stir electrolytes,
balance battery voltage, and accomplish chemical reactions. Equalizing charge

9
increases battery voltage, higher than the standard complement voltage, which
gasifies the battery electrolyte.
The controller will equalize the battery on the 28th of each month. The constant
equalization period is 0~180 minutes. Suppose the equalization isn't accomplished
at one-time. In that case, the equalization recharge time will be accumulated until
the set time is finished. Equalize and boost charges are not carried out constantly in
a full charge process to avoid too much gas precipitation or overheating of the
battery.
NOTE:
1) The battery voltage can't be steady in constant voltage due to ambient
circumstances or load working. The controller will accumulate and
calculate the time of constant voltage working. When the accumulated time
reaches 3 hours, the charging mode will turn to Float Charging.
2) If the controller time is not adjusted, the controller will charge the battery in
equalized charging mode once a month following the inner time.
C) Float Charging
After the Constant voltage stage, the controller will reduce the charging current to
the Float Voltage set point. This stage has no more chemical reactions, and all the
charge current transforms into heat and gas at this time. Then the controller reduces
the voltage to the floating stage, charging with a smaller voltage and current. It will
reduce the battery's temperature and prevent the battery's gassing and charging
simultaneously. The Float stage is to offset the power consumption caused by
self-consumption and small loads while maintaining full battery storage capacity.
In the Float charging stage, loads can obtain almost all power from solar panels. If
loads exceed the power, the controller can no longer maintain battery voltage in the
Float charging stage. Suppose the battery voltage remains below the Recharge
Voltage. In that case, the system will leave the Float charging stage and return to the

10
Bulk charging stage.

11
2 Installation Instructions
2.1 General Installation Notes
Be very careful when installing the batteries, especially flooded lead-acid
batteries. Please wear an eye protector, and have fresh water available to
wash and clean any contact with battery acid.
Keep the battery away from any metal objects, which may cause a short circuit
of the battery.
Explosive battery gases may come out from the battery during charging, ensure
the ventilation condition is good.
The controllers are intended for indoor use only. Prevent exposure to the
elements and do not allow water to enter the controller.
Ventilation is highly recommended if mounted in an enclosure. Never install the
controller in a sealed enclosure with flooded batteries! Battery fumes from
vented batteries will corrode and destroy the controller circuits.
Loose power connections and corroded wires may produce high heat that can
melt wire insulation, burn surrounding materials, or even cause a fire. Ensure
tight connections, use cable clamps to secure cables, and prevent them from
swaying in mobile applications.
Only lead-acid and lithium batteries that meet the controller requirement can be
charged.
Multiple models of controllers can be installed in parallel on the same battery
bank to achieve a higher charging current. Each controller must have its solar
module(s).
Select the system cables according to 5A/mm2or less current density following
Article 690 of the National Electrical Code, NFPA 70.

12
2.2 PV Array Requirements
Serial connection (string) of PV modules
As the core component of the PV system, the controller could be suitable for various
types of PV modules and maximize converting solar energy into electrical energy.
The series number of PV modules can be calculated according to the open-circuit
voltage (Voc) and the maximum power point voltage (Vmpp) of the MPPT controller.
The below table is for reference only.
System
voltage
36cell
Voc＜23V
48cell
Voc＜31V
54cell
Voc＜34V
60cell
Voc＜38V
MAX.
Best
MAX.
Best
MAX.
Best
MAX.
Best
12V
4
2
2
1
2
1
2
1
24V
6
3
4
2
4
2
3
2
System
voltage
72cell
Voc＜46V
96cell
Voc＜62V
Thin-Film Module
Voc＞80V
MAX.
Best
MAX.
Best
12V
2
1
1
1
1
24V
3
2
2
2
1
NOTE: The above parameter values are calculated under standard test conditions
(STC (Standard Test Condition): Irradiance 1000W/m2, Module Temperature 25℃,
Air Mass1.5.)
2.3 Wire Size
The wiring and installation methods must conform to national and local electrical
code requirements.
PV Wire Size
Since the PV array output varies with the PV module size, connection method, or
sunlight angle. The PV array ISC can calculate the minimum PV wire size. Please

13
refer to the value of ISC in the PV module specification. When the PV modules are
connected in series, the ISC equals any PV module's ISC. When the PV modules are
connected in parallel, the ISC equals the sum of the PV module's ISC. The PV array
ISC must not exceed the maximum PV input current. Please refer to the table below:
Model
Max. PV input current
Max. PV wire size (mm2/AWG)
Tracer4215BN
40A
16/6
NOTE: When the PV modules are connected in series, the open-circuit voltage of
the PV array must not exceed 138V (25℃).
Battery and Load Wire Size
The battery and load wire size must conform to the rated current. The reference size
is as below:
Model
Rated
charge
current
Rated
discharge
current
Battery wire
size
(mm2/AWG)
Load wire
size
(mm2/AWG)
Tracer4215BN
40A
40A
16/6
6/10
NOTE: The wire size is only for reference. Suppose there is a long distance
between the PV array, the controller, and the battery. In that case, larger wires can
be used to reduce the voltage drop and improve performance.
2.4 Mounting
WARNING
Explosive Risk!
Never install the controller in a sealed enclosure with flooded
batteries! Do not install in a confined area where battery gas can
accumulate.
Risk of electric shock!
Exercise caution when handling solar wiring. The solar PV array
can produce open-circuit voltages over 150V when in sunlight.

14
CAUTION
The controller requires at least 150mm of clearance above and
below for proper airflow. Ventilation is highly recommended if
mounted in an enclosure.
Figure 2-1 Mounting
1) Connect components to the charge controller in the sequence "①>②>③"
shown above and ensure that the electrode polarity is connected correctly.
Please don't connect the fast-acting fuse during the installation. When
disconnecting the system, the order will be reserved.
2) After installation, power the controller and check the battery indicator on the
controller; it will be green. If it's not green, please refer to chapter 4. Always
connect the battery first to allow the controller to recognize the system voltage.
3) The fast-acting fuse should be installed as close to the battery. The suggested
distance is within 150mm.

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4) The Tracer BN series is a negative ground controller. Any negative solar, load, or
battery connection can be earth grounded as required.
CAUTION
Unplug the RTS, and the battery's temperature will be 25 ºC.
Please connect the inverter to the battery rather than to the
controller if the inverter is necessary.
The RS485 and RTS ports are not SELV circuits; they must
have isolation between the port and where the end-user can
access them directly.

16
3 Operation
3.1 LED Indication
LED
Indication
Color
Indicator
Status
Green
On Solid
PV charges the battery
with a low current
Green
Slowly
Flashing(1Hz)
Normal charging
Green
OFF
1. No sunlight
2. Connection Error
3. Low PV voltage
Green
On Solid
Normal
Green
Slowly
Flashing(1Hz)
Full
Green
Fast Flashing(4Hz)
Overvoltage
Orange
On Solid
Under voltage
Red
On Solid
Over-discharge
Red
Flashing
Battery Overheating
Load Status
LED indicator
Red
On Solid
Load ON
Red
OFF
Load OFF
Red
Fast Flashing(4Hz)
Load Short Circuit
Red
Slowly
Flashing(1Hz)
Load Overload
Charging(green), battery (orange), and load(red)
indicators flash simultaneously
System voltage error
Charging(green) and battery indicator(orange) flash
Controller overheating