User Manual
InvertFlex 1K/2K/3K/5K
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Table of Contents
ABOUT THIS MANUAL ..................................................................................................................... 1
Purpose ................................................................................................................................................1
Scope ...................................................................................................................................................1
SAFETY INSTRUCTIONS .................................................................................................................. 1
INTRODUCTION .............................................................................................................................. 2
Features ...............................................................................................................................................2
Basic System Architecture ......................................................................................................................2
Product Overview ..................................................................................................................................3
INSTALLATION ................................................................................................................................ 4
Unpacking and Inspection ......................................................................................................................4
Preparation ...........................................................................................................................................4
Mounting the Unit ..................................................................................................................................4
Battery Connection ................................................................................................................................5
AC Input/Output Connection ..................................................................................................................7
PV Connection... ....................................................................................................................................9
Final Assembly .................................................................................................................................... 10
Communication Connection .................................................................................................................. 11
Dry Contact Signal ............................................................................................................................... 11
OPERATION ................................................................................................................................... 12
Power ON/OFF .................................................................................................................................... 12
Operation and Display Panel ................................................................................................................. 12
LCD Display Icons ................................................................................................................................ 13
LCD Setting ......................................................................................................................................... 15
Display Setting .................................................................................................................................... 23
Operating Mode Description ................................................................................................................. 25
Fault Reference Code ........................................................................................................................... 27
Warning Indicator ................................................................................................................................ 27
SPECIFICATIONS .......................................................................................................................... 28
Table 1 Line Mode Specifications .......................................................................................................... 28
Table 2 Inverter Mode Specifications..................................................................................................... 29
Table 3 Charge Mode Specifications ...................................................................................................... 30
Table 4 General Specifications .............................................................................................................. 30
TROUBLE SHOOTING .................................................................................................................... 31
Appendix: Approximate Back-up Time Table ................................................................................ 32
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ABOUT THIS MANUAL
Purpose
This manual describes the assembly, installation, operation and troubleshooting of this unit. Please read
this manual carefully before installations and operations. Keep this manual for future reference.
Scope
This manual provides safety and installation guidelines as well as information on tools and wiring.
SAFETY INSTRUCTIONS
WARNING: This chapter contains important safety and operating instructions. Read and
keep this manual for future reference.
1.
Before using the unit, read all instructions and cautionary markings on the unit, the batteries and all
appropriate sections of this manual.
2.
CAUTION - To reduce risk of injury, charge only deep-cycle lead acid type rechargeable batteries.
Other types of batteries may burst, causing personal injury and damage.
3.
Do not disassemble the unit. Take it to a qualified service center when service or repair is required.
Incorrect re-assembly may result in a risk of electric shock or fire.
4.
To reduce risk of electric shock, disconnect all wirings before attempting any maintenance or cleaning.
Turning off the unit will not reduce this risk.
5.
CAUTION – Only qualified personnel can install this device with battery.
6.
NEVER charge a frozen battery.
7.
For optimum operation of this inverter/charger, please follow required spec to select appropriate cable
size. It’s very important to correctly operate this inverter/charger.
8.
Be very cautious when working with metal tools on or around batteries. A potential risk exists to drop
a tool to spark or short circuit batteries or other electrical parts and could cause an explosion.
9.
Please strictly follow installation procedure when you want to disconnect AC or DC terminals. Please
refer to INSTALLATION section of this manual for the details.
10. Fuses (4 pieces of 40A, 32VDC for 1KVA/2KVA, 6 pieces of 40A, 32VDC for 3KVA, 1 piece of 200A,
64VDC for 5KVA) are provided as over-current protection for the battery supply.
11. GROUNDING INSTRUCTIONS -This inverter/charger should be connected to a permanent grounded
wiring system. Be sure to comply with local requirements and regulation to install this inverter.
12. NEVER cause AC output and DC input short circuited. Do NOT connect to the mains when DC input
short circuits.
13. Warning!! Only qualified service persons are able to service this device. If errors still persist after
following troubleshooting table, please send this inverter/charger back to local dealer or service center
for maintenance.
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INTRODUCTION
This is a multi-function inverter/charger, combining functions of inverter, solar charger and battery charger to
offer uninterruptible power support with portable size. Its comprehensive LCD display offers user-configurable
and easy-accessible button operation such as battery charging current, AC/solar charger priority, and
acceptable input voltage based on different applications.
Features

Pure sine wave inverter

Configurable input voltage range for home appliances and personal computers via LCD setting

Configurable battery charging current based on applications via LCD setting

Configurable AC/Solar Charger priority via LCD setting

Compatible to mains voltage or generator power

Auto restart while AC is recovering

Overload/ Over temperature/ short circuit protection

Smart battery charger design for optimized battery performance

Cold start function
Basic System Architecture
The following illustration shows basic application for this inverter/charger. It also includes following devices to
have a complete running system:
 Generator or Utility.
 PV modules (option)
Consult with your system integrator for other possible system architectures depending on your requirements.
This inverter can power all kind of appliances at home or office environment, including motor-type appliances
such as tube light, fan, refrigerator and air conditioner.
Figure 1 Hybrid Power System
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Product Overview
InvertFlex 5K single mode
InvertFlex 1K
InvertFlex 5K parallel model
1. LCD display
2. Status indicator
3. Charging indicator
4. Fault indicator
InvertFlex 2K/3K
NOTE: For parallel model installation and operation,
please check separate parallel installation guide for
the details.
5. Function buttons
6. Power on/off switch
7. AC input
8. AC output
9. PV input
10. Battery input
11. Circuit breaker
12. RS232 communication port
13. Parallel communication cable (only for InvertFlex 5K)
14. Current sharing cable (only for InvertFlex 5K)
15. Dry contact
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INSTALLATION
Unpacking and Inspection
Before installation, please inspect the unit. Be sure that nothing inside the package is damaged. You should
have received the following items inside of package:
 The unit x 1
 User manual x 1
 Communication cable x 1
 Software CD x 1
Preparation
Before connecting all wirings, please take off bottom cover by removing two screws as shown below.
Mounting the Unit
Consider the following points before selecting where to install:
 Do not mount the inverter on flammable construction
materials.
 Mount on a solid surface
 Install this inverter at eye level in order to allow the LCD
display to be read at all times.
 For proper air circulation to dissipate heat, allow a clearance
of approx. 20 cm to the side and approx. 50 cm above and
below the unit.
 The ambient temperature should be between 0°C and 55°C
to ensure optimal operation.
 The recommended installation position is to be adhered to
the wall vertically.
 Be sure to keep other objects and surfaces as shown in the
diagram to guarantee sufficient heat dissipation and to
have enough space for removing wires.
SUITABLE FOR MOUNTING ON CONCRETE OR OTHER NON-COMBUSTIBLE SURFACE ONLY.
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Install the unit by screwing three screws.
Battery Connection
CAUTION: For safety operation and regulation compliance, it’s requested to install a separate DC over-current
protector or disconnect device between battery and inverter. It may not be requested to have a disconnect
device in some applications, however, it’s still requested to have over-current protection installed. Please refer
to typical amperage in below table as required fuse or breaker size.
Ring terminal:
WARNING! All wiring must be performed by a qualified personnel.
WARNING! It's very important for system safety and efficient operation to use
appropriate cable for battery connection. To reduce risk of injury, please use the
proper recommended cable and terminal size as below.
Recommended battery cable and terminal size:
Model
InvertFlex
1K/2K
InvertFlex
3K
InvertFlex
5K
Typical
Amperage
66A
100A
84A
Battery
capacity
Wire Size
Cable
mm2
Ring Terminal
Dimensions
D (mm)
L (mm)
1*6AWG
14
6.4
29.2
2*10AWG
8
6.4
23.8
100AH
1*4AWG
22
6.4
33.2
200AH
2*8AWG
14
6.4
29.2
1*4AWG
22
6.4
33.2
2*8AWG
14
6.4
29.2
2*8AWG
14
6.4
29.2
100AH
200AH
Torque
value
2~ 3 Nm
2~ 3 Nm
2~ 3 Nm
Please follow below steps to implement battery connection:
1. Assemble battery ring terminal based on recommended battery cable and terminal size.
2. InvertFlex 1K model supports 12VDC system, InvertFlex 2K/3Kmodel supports 24VDC system and
InvertFlex 5K model supports 48VDC system. Connect all battery packs as below chart. It’s suggested to
connect at least 100Ah capacity battery for 1-3KVA model and at least 200Ah capacity battery for
InvertFlex 5K model.
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NOTE: Please only use sealed lead acid battery or sealed GEL/AGM lead-acid battery.
3. Insert the ring terminal of battery cable flatly into battery connector of inverter and make sure the bolts are
tightened with torque of 2-3 Nm. Make sure polarity at both the battery and the inverter/charge is correctly
connected and ring terminals are tightly screwed to the battery terminals.
WARNING: Shock Hazard
Installation must be performed with care due to high battery voltage in series.
CAUTION!! Do not place anything between the flat part of the inverter terminal and the ring
terminal. Otherwise, overheating may occur.
CAUTION!! Do not apply anti-oxidant substance on the terminals before terminals are
connected tightly.
CAUTION!! Before making the final DC connection or closing DC breaker/disconnector, be sure
positive (+) must be connected to positive (+) and negative (-) must be connected to negative
(-).
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AC Input/Output Connection
CAUTION!! Before connecting to AC input power source, please install a separate AC breaker between
inverter and AC input power source. This will ensure the inverter can be securely disconnected during
maintenance and fully protected from over current of AC input. The recommended spec of AC breaker is 10A
for InvertFlex 1K, 20A for InvertFlex 2K, 32A for InvertFlex 3K , 50A for InvertFlex 5K.
CAUTION!! There are two terminal blocks with “IN” and “OUT” markings. Please do NOT mis-connect input
and output connectors.
WARNING! All wiring must be performed by a qualified personnel.
WARNING! It's very important for system safety and efficient operation to use appropriate cable for AC input
connection. To reduce risk of injury, please use the proper recommended cable size as below.
Suggested cable requirement for AC wires
Model
Gauge
Torque Value
InvertFlex 1K
16 AWG
0.5~ 0.6 Nm
InvertFlex 2K
14 AWG
0.8~ 1.0 Nm
InvertFlex 3K
12 AWG
1.2~ 1.6 Nm
InvertFlex 5K
8 AWG
1.4~1.6Nm
Please follow below steps to implement AC input/output connection:
1. Before making AC input/output connection, be sure to open DC protector or disconnector first.
2. Remove insulation sleeve 10mm for six conductors. And shorten phase L and neutral conductor N 3 mm.
3. Insert AC input wires according to polarities indicated on terminal block and tighten the terminal screws. Be
sure to connect PE protective conductor ( ) first.
→Ground (yellow-green)
L→LINE (brown or black)
N→Neutral (blue)
InvertFlex 1K
InvertFlex 2K/3K/5K
WARNING:
Be sure that AC power source is disconnected before attempting to hardwire it to the unit.
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4. Then, insert AC output wires according to polarities indicated on terminal block and tighten terminal screws.
Be sure to connect PE protective conductor (
) first.
→Ground (yellow-green)
L→LINE (brown or black)
N→Neutral (blue)
InvertFlex 1K
InvertFlex 2K/3K/5K
5. Make sure the wires are securely connected.
CAUTION: Important
Be sure to connect AC wires with correct polarity. If L and N wires are connected reversely, it may cause
utility short-circuited when these inverters are worked in parallel operation.
CAUTION: Appliances such as air conditioner are required at least 2~3 minutes to restart because it’s required
to have enough time to balance refrigerant gas inside of circuits.
If a power shortage occurs and recovers in a
short time, it will cause damage to your connected appliances. To prevent this kind of damage, please check
manufacturer of air conditioner if it’s equipped with time-delay function before installation. Otherwise, this
inverter/charger will trig overload fault and cut off output to protect your appliance but sometimes it still causes
internal damage to the air conditioner.
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PV Connection
CAUTION: Before connecting to PV modules, please install separately a DC circuit breaker between inverter
and PV modules.
WARNING! All wiring must be performed by a qualified personnel.
WARNING! It's very important for system safety and efficient operation to use appropriate cable for PV
module connection. To reduce risk of injury, please use the proper recommended cable size as below.
Typical Amperage
Gauge
Torque Value
50A
8 AWG
1.4~1.6 Nm
PV Module Selection:
When selecting proper PV modules, please be sure to consider below requirements first:
1. Open circuit Voltage (Voc) of PV modules not exceeds max. PV array open circuit voltage of inverter.
INVERTER MODEL
InvertFlex
InvertFlex
1K
InvertFlex
2K
InvertFlex
3K
5K
Solar Charger
Charging Current (PWM)
System DC Voltage
Operating Voltage Range
Max. PV Array Open Circuit Voltage
50Amp
12Vdc
24Vdc
48Vdc
15~18Vdc
30~32Vdc
60~72vdc
40Vdc
60Vdc
105Vdc
2. Max. Power Voltage (Vmpp) of PV modules should be close to best Vmp of inverter or within Vmp range to
get best performance. If one PV module can not meet this requirement, it’s necessary to have several PV
modules in series connection. Refer to below table.
Model
Best Vmp
Vmp range
InvertFlex 1K
15Vdc
15V~18V
InvertFlex 2K/3K
30Vdc
30V~32V
InvertFlex 5K
60Vdc
56V~72V
Note: * Vmp: panel max power point voltage.
The PV charging efficiency is maximized while PV system voltage is close to Best Vmp.
Maximum PV module numbers in Series: Vmpp of PV module * X pcs ≒ Best Vmp of Inverter or Vmp
range
PV module numbers in Parallel: Max. charging current of inverter / Impp
Total PV module numbers = maximum PV module numbers in series * PV module numbers in
parallel
Take 1KVA inverter as an example to select proper PV modules. After considering Voc of PV module not exceeds
40Vdc and max. Vmpp of PV module close to 15Vdc or within 13Vdc ~ 18Vdc, we can choose PV module with
below specification.
Maximum Power (Pmax)
85W
Max. PV module numbers in series
1  17.6 x 1 ≒ 15 ~ 18
Max. Power Voltage Vmpp(V) 17.6V
Max. Power Current Impp(A) 4.83A
PV module numbers in parallel
10  50 A / 4.83
Open Circuit Voltage Voc(V)
21.6V
Total PV module numbers
Short Circuit Current Isc(A)
5.03A
1 x 10 = 10
Maximum PV module numbers in Series: 1
PV module numbers in Parallel: 10
Total PV module numbers: 1 x 10 = 10
Take InvertFlex 2K/InvertFlex 3K inverter as an example to select proper PV module. After considering Voc of PV
module not exceed 60Vdc and max. Vmpp of PV module close to 30Vdc or within 30Vdc ~ 32Vdc, we can
choose PV module with below specification.
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Maximum Power (Pmax)
Max. Power Voltage Vmpp(V)
Max. Power Current Impp(A)
Open Circuit Voltage Voc(V)
Short Circuit Current Isc(A)
260W
30.9V
8.42A
37.7V
8.89A
Max. PV module numbers in series
1  30.9 x 1 ≒ 30 ~ 32
PV module numbers in parallel
6  50 A / 8.42
Total PV module numbers
1x6=6
Maximum PV module numbers in Series: 1
PV module numbers in Parallel: 6
Total PV module numbers: 1 x 6 = 6
Take InvertFlex 5K model inverter as an example to select proper PV module. After considering Voc of PV
module not exceed 105Vdc and max. Vmpp of PV module close to 60Vdc or within 56Vdc ~ 72Vdc, we can
choose PV module with below specification.
Maximum Power (Pmax)
260W
Max. PV module numbers in series
2  30.9 x 2 ≒ 56 ~ 72
Max. Power Voltage Vmpp(V) 30.9V
Max. Power Current Impp(A) 8.42A
PV module numbers in parallel
6  50 A / 8.42
Open Circuit Voltage Voc(V)
37.7V
Total PV module numbers
Short Circuit Current Isc(A)
8.89A
2 x 6 = 12
Maximum PV module numbers in Series: 2
PV module numbers in Parallel: 6
Total PV module numbers: 2 x 6 = 12
Please follow below steps to implement PV module connection:
1. Remove insulation sleeve 10 mm for positive and negative conductors.
2. Check correct polarity of connection cable from PV modules and PV input
connectors. Then, connect positive pole (+) of connection cable to positive
pole (+) of PV input connector. Connect negative pole (-) of connection
cable to negative pole (-) of PV input connector.
3. Make sure the wires are securely connected.
Final Assembly
After connecting all wirings, please put bottom cover back by screwing two screws as shown below.
InvertFlex 1K/2K/3K
InvertFlex 5K
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Communication Connection
Please use supplied communication cable to connect to inverter and PC. Insert bundled CD into a computer and
follow on-screen instruction to install the monitoring software. For the detailed software operation, please
check user manual of software inside of CD.
Dry Contact Signal
There is one dry contact (3A/250VAC) available on the rear panel. It could be used to deliver signal to external
device when battery voltage reaches warning level.
Unit Status
Power Off
Condition
Dry contact port:
NC & C
NO & C
Unit is off and no output is powered.
Close
Open
Output is powered from Utility.
Close
Open
Open
Close
Close
Open
Open
Close
Close
Open
Output
is
powered
Program
01
set as Utility
Battery voltage < Low DC
warning voltage
from Battery
Battery voltage > Setting
or Solar.
value in Program 13 or
battery
Power On
charging
reaches
floating stage
Program 01 is
Battery voltage < Setting
set as SBU or
value in Program 12
Solar first
Battery voltage > Setting
value in Program 13 or
battery charging reaches
floating stage
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OPERATION
Power ON/OFF
Once the unit has been properly installed and the batteries are connected well, simply press On/Off switch
(located on the button of the case) to turn on the unit.
Operation and Display Panel
The operation and display panel, shown in below chart, is on the front panel of the inverter. It includes
three indicators, four function keys and a LCD display, indicating the operating status and input/output
power information.
LCD display
LED indicators
Function keys
LED Indicator
LED Indicator
Green
Green
Red
Messages
Solid On
Output is powered by utility in Line mode.
Flashing
Output is powered by battery or PV in battery mode.
Solid On
Battery is fully charged.
Flashing
Battery is charging.
Solid On
Fault occurs in the inverter.
Flashing
Warning condition occurs in the inverter.
Function Keys
Function Key
Description
ESC
To exit setting mode
UP
To go to previous selection
DOWN
To go to next selection
ENTER
To confirm the selection in setting mode or enter setting mode
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LCD Display Icons
Icon
Function description
Input Source Information
Indicates the AC input.
Indicates the PV input
Indicate input voltage, input frequency, PV voltage, battery voltage and
charger current.
Configuration Program and Fault Information
Indicates the setting programs.
Indicates the warning and fault codes.
Warning:
Fault:
flashing with warning code.
lighting with fault code
Output Information
Indicate output voltage, output frequency, load percent, load in VA, load in
Watt and discharging current.
Battery Information
Indicates battery level by 0-24%, 25-49%, 50-74% and 75-100% in battery
mode and charging status in line mode.
In AC mode, it will present battery charging status.
Status
Battery voltage
<2V/cell
Constant
2 ~ 2.083V/cell
Current mode /
Constant
Voltage mode
LCD Display
4 bars will flash in turns.
Bottom bar will be on and the other three
bars will flash in turns.
Bottom two bars will be on and the other
two bars will flash in turns.
Bottom three bars will be on and the top
2.083 ~ 2.167V/cell
> 2.167 V/cell
bar will flash.
Floating mode. Batteries are fully charged.
4 bars will be on.
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In battery mode, it will present battery capacity.
Load Percentage
Battery Voltage
LCD Display
< 1.717V/cell
1.717V/cell ~ 1.8V/cell
Load >50%
1.8 ~ 1.883V/cell
> 1.883 V/cell
< 1.817V/cell
1.817V/cell ~ 1.9V/cell
50%> Load > 20%
1.9 ~ 1.983V/cell
> 1.983
< 1.867V/cell
1.867V/cell ~ 1.95V/cell
Load < 20%
1.95 ~ 2.033V/cell
> 2.033
Load Information
Indicates overload.
Indicates the load level by 0-24%, 25-50%, 50-74% and 75-100%.
0%~25%
25%~50%
50%~75%
75%~100%
Mode Operation Information
Indicates unit connects to the mains.
Indicates unit connects to the PV panel.
Indicates load is supplied by utility power.
Indicates the utility charger circuit is working.
Indicates the DC/AC inverter circuit is working.
Mute Operation
Indicates unit alarm is disabled.
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LCD Setting
After pressing and holding ENTER button for 3 seconds, the unit will enter setting mode. Press “UP” or “DOWN”
button to select setting programs. And then, press “ENTER” button to confirm the selection or ESC button to
exit.
Setting Programs:
Program
Description
Selectable option
Escape
00
Exit setting mode
Solar energy provides power to the
loads as first priority.
If solar energy is not sufficient to
power all connected loads, battery
Solar first
energy will supply power the loads at
the same time.
Utility provides power to the loads only
when any one condition happens:
- Solar energy is not available
- Battery voltage drops to low-level
warning voltage or the setting point in
program 12.
Output source priority:
01
To configure load power
Utility will provide power to the loads
Utility first (default)
source priority
as first priority.
Solar and battery energy will provide
power to the loads only when utility
power is not available.
Solar energy provides power to the
loads as first priority.
If solar energy is not sufficient to
SBU priority
power all connected loads, battery
energy will supply power to the loads
at the same time.
Utility provides power to the loads only
when battery voltage drops to either
low-level warning voltage or the
setting point in program 12.
Available options only for InvertFlex 1K/2K/3K model
02
Maximum charging current:
To configure total charging
current for solar and utility
chargers.
(Max. charging current =
utility charging current +
solar charging current)
10A (Only available
for 1K model)
30A
20A
40A
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50A (default)
Available options only for InvertFlex 5K model
60A
70A
80A
90A
100A
110A
Appliances (default)
If selected, acceptable AC input
voltage range will be within
03
AC input voltage range
90-280VAC.
UPS
If selected, acceptable AC input
voltage range will be within
170-280VAC.
04
Power saving mode
enable/disable
Saving mode disable
If disabled, no matter connected load
(default)
is low or high, the on/off status of
inverter output will not be effected.
Saving mode enable
If enabled, the output of inverter will
be off when connected load is pretty
low or not detected.
05
Battery type
AGM (default)
Flooded
User-Defined
If “User-Defined” is selected, battery
charge voltage and low DC cut-off
voltage can be set up in program 26,
27 and 29.
Restart disable
06
Auto restart when overload
occurs
(default)
Restart disable
07
Auto restart when over
temperature occurs
Restart enable
(default)
50Hz (default)
09
Restart enable
60Hz
Output frequency
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Available options in InvertFlex 1K model:
10A
20A (default)
Available options in InvertFlex 2K/3K model:
20A
Maximum utility charging
current
11
Note: If setting value in
program 02 is smaller than
that in program in 11, the
inverter will apply charging
current from program 02 for
utility charger.
30A (default)
Available options in 5K model:
2A
10A
20A
30A (default)
40A
50A
60A
Available options in InvertFlex 1K model:
12
Setting voltage point back
to utility source when
selecting “SBU priority” or
“Solar first” in program 01.
11.0V
11.3V
11.5V (default)
11.8V
12.0V
12.3V
12.5V
12.8V
Available options in InvertFlex 2K/3K model:
22.0V
22.5V
23.0V (default)
23.5V
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24.0V
24.5V
25.0V
25.5V
Available options in InvertFlex 5K model:
44V
45V
46V (default)
47V
48V
49V
50V
51V
Available options in InvertFlex 1K model:
Setting voltage point back
13
to battery mode when
Battery fully charged
12.0V
12.3V
12.5V
12.8V
13.0V
13.3V
13.5V (default)
13.8V
14.0V
selecting “SBU priority” or
“Solar first” in program 01.
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14.3V
14.5V
Available options in InvertFlex 2K/3K model:
Setting voltage point back
13
Battery fully charged
24V
24.5V
25V
25.5V
26V
26.5V
27V (default)
27.5V
28V
28.5V
29V
to battery mode when
selecting “SBU priority” or
“Solar first” in program 01.
Available options in InvertFlex 5K model:
Battery fully charged
48V
49V
50V
51V
52V
53V
54V (default)
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55V
56V
57V
58V
If this inverter/charger is working in Line, Standby or Fault
mode, charger source can be programmed as below:
Solar first
Solar energy will charge battery as
first priority.
Utility will charge battery only when
solar energy is not available.
Utility first
Utility will charge battery as first
priority.
Solar energy will charge battery
16
Charger source priority:
only when utility power is not
To configure charger source
available.
priority
Solar and Utility
Solar energy and utility will charge
(default)
battery at the same time.
Only Solar
Solar energy will be the only
charger source no matter utility is
available or not.
If this inverter/charger is working in Battery mode or Power
saving mode, only solar energy can charge battery. Solar
energy will charge battery if it's available and sufficient.
18
19
Alarm on (default)
Alarm off
Return to default
If selected, no matter how users
display screen
switch display screen, it will
(default)
automatically return to default
Alarm control
display screen (Input voltage
Auto return to default
display screen
/output voltage) after no button is
pressed for 1 minute.
Stay at latest screen
If selected, the display screen will
stay at latest screen user finally
switches.
Backlight on
20
Backlight control
22
Beeps while primary source
is interrupted
Backlight off
(default)
Alarm on (default)
Alarm off
20
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23
Overload bypass:
When enabled, the unit will
transfer to line mode if
overload occurs in battery
mode.
Bypass disable
(default)
Record enable
25
Bypass enable
Record disable (default)
Record Fault code
1KVA default setting: 14.1V
2K/3KVA default setting: 28.2V
26
Bulk charging voltage
(C.V voltage)
5KVA default setting: 56.4V
If self-defined is selected in program 5, this program can
be set up. Setting range is from 12.0V to 14.6V for
InvertFlex 1K model, 24.0V to 29.2V for InvertFlex 2K/3K
model and 48.0V to 58.4V for InvertFlex 5K model.
Increment of each click is 0.1V.
1KVA default setting: 13.5V
2K/3KVA default setting: 27.0V
27
Floating charging voltage
5KVA default setting: 54.0V
If self-defined is selected in program 5, this program can
be set up. Setting range is from 12.0V to 14.6V for
InvertFlex 1K model, 24.0V to 29.2V for InvertFlex 2K/3K
model and 48.0V to 58.4V for InvertFlex 5K model.
Increment of each click is 0.1V.
21
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1KVA default setting: 10.5V
2K/3KVA default setting: 21.0V
5KVA default setting: 42.0V
29
Low DC cut-off voltage
If self-defined is selected in program 5, this program can
be set up. Setting range is from 10.0V to 12.0V for
InvertFlex 1K model, 20.0V to 24.0V for InvertFlex 2K/3K
model and 40.0V to 48.0V for InvertFlex 5K model.
Increment of each click is 0.1V. Low DC cut-off voltage will
be fixed to setting value no matter what percentage of load
is connected.
Solar power balance
enable (Default):
31
Solar power balance:
When enabled, solar input
power will be automatically
adjusted according to
connected load power.
(Only available for
InvertFlex 5KVA model)
Solar power balance
disable:
If selected, solar input power will
be automatically adjusted
according to the following formula:
Max. input solar power = Max.
battery charging power +
Connected load power.
If selected, the solar input power
will be the same to max. battery
charging power no matter how
much loads are connected. The
max. battery charging power will
be based on the setting current in
program 02.
(Max. solar power = Max. battery
charging power)
22
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Display Setting
The LCD display information will be switched in turns by pressing “UP” or “DOWN” key. The selectable
information is switched as below order: input voltage, input frequency, PV voltage, charging current,
battery voltage, output voltage, output frequency, load percentage, load in Watt, load in VA, load in Watt,
DC discharging current, main CPU Version and second CPU Version.
Selectable information
LCD display
Input Voltage=230V, output voltage=230V
Input voltage/Output voltage
(Default Display Screen)
Input frequency=50Hz
Input frequency
PV voltage=60V
PV voltage
Charging current=50A
Charging current
Battery voltage=25.5V, discharging current=1A
Battery voltage/ DC discharging current
Output frequency=50Hz
Output frequency
23
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Load percent=70%
Load percentage
When
connected
load
is
lower
than
InvertFlex 1k, load in VA will present xxxVA like
below chart.
Load in VA
When load is larger than 1kVA (≧1KVA), load in
VA will present x.xkVA like below chart.
When load is lower than 1kW, load in W will
present xxxW like below chart.
Load in Watt
When load is larger than 1kW (≧1KW), load in W
will present x.xkW like below chart.
Main CPU version 00014.04
Main CPU version checking
24
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Secondary CPU version 00003.03
Secondary CPU version checking
Operating Mode Description
Operation mode
Description
LCD display
Charging by utility and PV energy.
Standby mode / Power
saving mode
Charging by utility.
Note:
*Standby mode: The inverter is
not turned on yet but at this
No output is supplied by the
time, the inverter can charge
unit but it still can charge
battery without AC output.
batteries.
Charging by PV energy.
*Power saving mode: If
enabled, the output of inverter
will be off when connected load
is pretty low or not detected.
No charging.
Charging by utility and PV energy. (Only
available in InvertFlex 1K/2K/3K model)
Fault mode
Charging
Note:
*Fault mode: Errors are caused
by inside circuit error or external
reasons such as over
by
utility.
(Only
available
in
InvertFlex 1K/2K/3K model)
PV energy and utility can
charge batteries.
temperature, output short
circuited and so on.
Charging by PV energy.
25
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Operation mode
Description
Fault mode
PV energy and utility can
Note:
charge batteries.
*Fault mode: Errors are caused
by inside circuit error or external
reasons such as over
temperature, output short
circuited and so on.
LCD display
No charging.
Utility can power loads when
the unit starts up without
Power from utility
battery. (Only available
InvertFlex 5K model with
single operation)
Charging by utility and PV energy.
The unit will provide output
Line Mode
power from the mains. It will
also charge the battery at
Charging by utility.
line mode.
Power from battery and PV energy.
The unit will provide output
Battery Mode
power from battery and PV
power.
Power from battery only.
26
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Fault Reference Code
Fault Code
Fault Event
01
Fan is locked when inverter is off.
02
Over temperature
03
Battery voltage is too high
04
Battery voltage is too low
05
06
Icon on
Output short circuited or over temperature is detected
by internal converter components.
Output voltage is abnormal. (For InvertFlex 1K/2K/3K
model)
Output voltage is too high. InvertFlex(5K model)
07
Overload time out
08
Bus voltage is too high
09
Bus soft start failed
11
Main relay failed
51
Over current or surge
52
Bus voltage is too low
53
Inverter soft start failed
55
Over DC voltage in AC output
56
Battery connection is open
57
Current sensor failed
58
Output voltage is too low
NOTE: Fault codes 51, 52, 53, 55, 56, 57 and 58 are only available in 5K model.
Warning Indicator
Warning
Code
Warning Event
Audible Alarm
01
Fan is locked when
inverter is on.
Beep three times every
second
03
Battery is over-charged
Beep once every second
04
Low battery
Beep once every second
07
Overload
Beep once every 0.5 second
10
Output power derating
Beep twice every 3 seconds
Icon flashing
27
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SPECIFICATIONS
Table 1 Line Mode Specifications
INVERTER MODEL
InvertFlex
InvertFlex InvertFlex
1K
2K
Input Voltage Waveform
InvertFlex
3K
5K
Sinusoidal (utility or generator)
Nominal Input Voltage
230Vac
170Vac±7V (UPS);
Low Loss Voltage
90Vac±7V (Appliances)
180Vac±7V (UPS);
Low Loss Return Voltage
100Vac±7V (Appliances)
High Loss Voltage
280Vac±7V
High Loss Return Voltage
270Vac±7V
Max AC Input Voltage
300Vac
Nominal Input Frequency
50Hz / 60Hz (Auto detection)
Low Loss Frequency
40±1Hz
Low Loss Return Frequency
42±1Hz
High Loss Frequency
65±1Hz
High Loss Return Frequency
63±1Hz
Output Short Circuit Protection
Circuit Breaker
Efficiency (Line Mode)
>95% ( Rated R load, battery full charged )
10ms typical (UPS);
Transfer Time
20ms typical (Appliances)
Output Power
Output power derating:
Rated Power
When AC input voltage drops to 170V,
the output power will be derated.
50% Power
90V
170V
280V
Input Voltage
28
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Table 2 Inverter Mode Specifications
INVERTER MODEL
Rated Output Power
InvertFlex
InvertFlex
InvertFlex
InvertFlex
1K
2K
3K
5K
1KVA/0.8KW
2KVA/1.6KW
3KVA/2.4KW
Output Voltage Waveform
Pure Sine Wave
Output Voltage Regulation
230Vac±5%
Output Frequency
50Hz
Peak Efficiency
90%
Overload Protection
5s@≥150% load; 10s@110%~150% load
2* rated power for 5 seconds
Surge Capacity
Nominal DC Input Voltage
5KVA/4KW
12Vdc
24Vdc
48Vdc
11.5Vdc
23.0Vdc
46.0Vdc
@ load < 20%
11.0Vdc
22.0Vdc
44.0Vdc
@ 20% ≤ load < 50%
10.7Vdc
21.4Vdc
42.8Vdc
@ load ≥ 50%
10.1Vdc
20.2Vdc
40.4Vdc
@ load < 20%
11.5Vdc
23.0Vdc
46.0Vdc
@ 20% ≤ load < 50%
11.2Vdc
22.4Vdc
44.8Vdc
@ load ≥ 50%
10.6Vdc
21.2Vdc
42.4Vdc
@ load < 20%
10.5Vdc
21.0Vdc
42.0Vdc
@ 20% ≤ load < 50%
10.2Vdc
20.4Vdc
40.8Vdc
@ load ≥ 50%
9.6Vdc
19.2Vdc
38.4Vdc
High DC Recovery Voltage
14.5Vdc
29Vdc
58Vdc
High DC Cut-off Voltage
15.5Vdc
31Vdc
60Vdc
No Load Power Consumption
<15W
<20W
<50W
Saving Mode Power Consumption
<5W
<10W
<15W
Cold Start Voltage
Low DC Warning Voltage
Low DC Warning Return Voltage
Low DC Cut-off Voltage
29
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Table 3 Charge Mode Specifications
INVERTER MODEL
InvertFlex
InvertFlex
InvertFlex
InvertFlex
1K
2K
3K
5K
Charging Algorithm
3-Step
Utility Charging Mode
AC Charging Current
Bulk Charging
Voltage
Flooded Battery
AGM / Gel
Battery
Floating Charging Voltage
10/20Amp
20/30Amp (@VI/P=230Vac)
2/10/20/30/40/50/
60Amp (@VI/P=230Vac)
14.6
29.2
58.4
14.1
28.2
56.4
13.5Vdc
27Vdc
54Vdc
Battery Voltage, per cell
Charging Current, %
2.43Vdc (2.35Vdc)
Voltage
2.25Vdc
100%
Charging Curve
50%
T0
T1
T1 = 10* T0, minimum 10mins, maximum 8hrs
Current
Bulk
(Constant Current)
Absorption
(Constant Voltage)
Time
Maintenance
(Floating)
Solar Charging Mode
Charging Current (PWM)
System DC Voltage
Operating Voltage Range
Max. PV Array Open Circuit Voltage
Standby Power Consumption
50Amp
12Vdc
24Vdc
48Vdc
15~18Vdc
30~32Vdc
60~72vdc
40Vdc
60Vdc
105Vdc
1W
2W
DC Voltage Accuracy
+/-0.3%
Joint Utility and Solar Charging
INVERTER MODEL
InvertFlex
InvertFlex
Invert Flex
InvertFlex
1K
2K
3K
5K
Max Charging Current
50Amp
110Amp
Default Charging Current
50Amp
50Amp
Table 4 General Specifications
INVERTER MODEL
InvertFlex
InvertFlex
Invert Flex
InvertFlex
1K
2K
3K
5K
Safety Certification
CE
Operating Temperature Range
0°C to 55°C
Storage temperature
-15°C~ 60°C
Dimension (D*W*H), mm
95 x 240 x
316
Net Weight, kg
5.0
100 x 272 x 355
6.4
6.9
120 x 295 x 468
9.8
30
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TROUBLE SHOOTING
Problem
Unit shuts down
automatically
during startup
process.
No response after
power on.
Mains exist but the
unit works in
battery mode.
When the unit is
turned on, internal
relay is switched on
and off repeatedly.
LCD/LED/Buzzer
Explanation / Possible cause
LCD/LEDs and buzzer
will be active for 3
seconds and then
complete off.
The battery voltage is too low
(<1.91V/Cell)
1. Re-charge battery.
2. Replace battery.
No indication.
1. The battery voltage is far too
low. (<1.4V/Cell)
2. Battery polarity is connected
reversed.
1. Check if batteries and the
wiring are connected well.
2. Re-charge battery.
3. Replace battery.
Input voltage is
displayed as 0 on the
LCD and green LED is
flashing.
Input protector is tripped
Check if AC breaker is tripped
and AC wiring is connected
well.
Green LED is flashing.
Insufficient quality of AC power.
(Shore or Generator)
Green LED is flashing.
Set “Solar First” as the priority of
output source.
LCD display and LEDs
are flashing
Battery is disconnected.
Fault code 07
Overload error. The inverter is
overload 110% and time is up.
1. Check if AC wires are too
thin and/or too long.
2. Check if generator (if
applied) is working well or if
input voltage range setting is
correct. (UPSAppliance)
Change output source priority
to Utility first.
Check if battery wires are
connected well.
Reduce the connected load by
switching off some
equipment.
Check if wiring is connected
well and remove abnormal
load.
Output short circuited.
Fault code 05
Temperature of internal converter
component is over 120°C. (Only
available for 1-3KVA models)
Internal temperature of inverter
component is over 100°C.
Check whether the air flow of
the unit is blocked or whether
the ambient temperature is
too high.
Battery is over-charged.
Return to repair center.
The battery voltage is too high.
Check if spec and quantity of
batteries are meet
requirements.
Fault code 01
Fan fault
Replace the fan.
Fault code 06/58
Output abnormal (Inverter voltage
below than 190Vac or is higher
than 260Vac)
1. Reduce the connected
load.
2. Return to repair center
Fault code
08/09/53/57
Internal components failed.
Return to repair center.
Fault code 51
Over current or surge.
Fault code 52
Bus voltage is too low.
Fault code 55
Output voltage is unbalanced.
Fault code 56
Battery is not connected well or
fuse is burnt.
Fault code 02
Buzzer beeps
continuously and
red LED is on.
What to do
Fault code 03
Restart the unit, if the error
happens again, please return
to repair center.
If the battery is connected
well, please return to repair
center.
31
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Appendix: Approximate Back-up Time Table
Model
Load (VA)
InvertFlex 1K
Model
InvertFlex 3K
Model
766
1610
200
335
766
300
198
503
400
139
339
500
112
269
600
95
227
700
81
176
800
62
140
900
55
125
1000
50
112
Backup Time @ 24Vdc 100Ah (min)
Backup Time @ 24Vdc 200Ah (min)
200
766
1610
400
335
766
600
198
503
800
139
339
1000
112
269
1200
95
227
1400
81
176
1600
62
140
1800
55
125
2000
50
112
300
449
1100
600
222
525
900
124
303
1200
95
227
1500
68
164
1800
56
126
2100
48
108
2400
35
94
2700
31
74
3000
28
67
Load (VA)
InvertFlex 5K
Backup Time @ 12Vdc 200Ah (min)
100
Load (VA)
InvertFlex 2K
Backup Time @ 12Vdc 100Ah (min)
Backup Time @ 48Vdc 100Ah (min)
Backup Time @ 48Vdc 200Ah (min)
500
613
1288
1000
268
613
1500
158
402
2000
111
271
2500
90
215
3000
76
182
3500
65
141
4000
50
112
4500
44
100
5000
40
90
Note: Backup time depends on the quality of the battery, age of battery and type of battery.
Specifications of batteries may vary depending on different manufacturers.
32
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