FOXPOWER Ultra UL1741 User manual

FULAGDA1512A, FULAGDA252 4 A, FULAGDA35 2 4 A
FULAGDA452 4 A, FULAGDA35 4 8 A, FU LAGDA45 48A
FULAGDA604 8 D, FU LAGDA15 12T , FULAGDA2524T
FULAGDA352 4 T , FU LAGDA4524T, FULAGDA35 2 4 D
FULAGDA354 8 D, FU LAGDA45 24D, FU LAGDA4548D
User's Guide
Ultra UL1741
Model Numbers
Pure Sine Wave Inverter Chargers
Your best partner for power

Part Nunber Explain:
610-11000-00 FULAGDA1512A
June 2017 Rev A
FULAGDA1512A, FULAGDA2524A, FULAGDA3524A, FULAGDA4524A, FULAGDA3548A
FULAGDA4548A, FULAGDA6048D, FULAGDA1512T, FULAGDA2524T, FULAGDA3524T
FULAGDA4524T, FULAGDA3524D, FULAGDA4524D, FULAGDA3548D, FULAGDA4548D
Contact information
Telephone: [phone]
Web: www.fox-power.com
Copyright © 2017-2018 Foxpower Technology. All Rights Reserved. All trademarks
are owned by Foxpower Technology or its affiliated companies.
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Series Number
Product Number
Purchased From
Purchased Date
ULAGDA
F
15
12
A
A: Advance
D: Split Phase Output
T: Without power save mode
DC voltage: 12-12Vdc;
Power rating: 15-1500W, 25-2500W,
35-3500W, 45 -4500W, 60 -6000W
F: Foxpower
UL1741

Purpose
Scope
Audience
• Selecting and using Personal Protective Equipment (PPE).
Conventions Used
The following conventions are used in this guide.
Related Information
About This Guide
The purpose of this Installation Guide is to provide explanations and
procedures for installing the Ultra UL1741 Inverter/Charger.
DANGER
DANGER indicates an imminently hazardous situation, which, if not
avoided, will result in death or serious injury.
• Installing electrical equipment and PV power systems (up to 1000 volts).
• Applying all applicable installation codes.
NOTICE
• Analyzing and reducing the hazards involved in performing electrical
work.
NOTICE indicates a potentially hazardous situation, which, if not
avoided, can result in equipment damage.
IMPORTANT: These notes describe things which are important for you
to know, however, they are not as serious as a caution or warning.
The Guide provides safety and installation guidelines as well as information
on con tools and wiring. It does not provide details about particular brands
of batteries. You need to consult individual battery manufacturers for this
information.
WARNING
WARNING indicates a potentially hazardous situation, which, if not
avoided, can result in death or serious injury.
CAUTION
The information in this Guide is intended for qualified personnel. Qualified
personnel have training, knowledge, and experience in:
CAUTION indicates a potentially hazardous situation, which, if not
avoided, can result in moderate or minor injury.
You can find more information about Foxpower-branded products and
services at www.fox-power.com

Important Safety Instructions
IMPORTANT: READ AND SAVE THIS INSTALLATION GUIDE FOR FUTURE
REFERENCE.
DANGER
This chapter contains important safety and installation instructions for the
Ultra UL1741 Inverter/Charger (Ultra UL1741). Each time, before using the
Ultra UL1741, READ ALL instructions and cautionary markings on or
provided with the inverter/charger, the batteries, and all appropriate
sections of this guide.
ELECTRICAL SHOCK HAZARD
• Do not expose the Ultra UL1741 to rain, snow, spray, or bilge water.
This inverter/charger is designed for marine applications only when
additional drip protection is installed in certain orientations. See “
Mounting Orientations” on page 24 for more information.
• Do not operate the inverter/charger if it has received a sharp blow,
been dropped, has cracks or openings in the enclosure including if the
AC terminal cover has been lost, damaged, or will not close, or
otherwise damaged in any other way.
• Do not disassemble the inverter/charger. Internal capacitors remain
charged after all power is disconnected.
• Disconnect both AC and DC power from the inverter/charger before
attempting any maintenance or cleaning or working on any circuits
connected to the inverter/charger. The INVERTER ENABLE button on
the front panel does not function like a power switch that energizes or
de-energizes the unit arbitrarily. When AC and DC power sources are
connected and present, the unit is always energized.
• Do not operate the inverter/charger with damaged or substandard
wiring. Make sure that all wiring is in good condition and is not
undersized.
Failure to follow these instructions will result in death or serious injury.
NOTE: The Ultra UL1741 contains no user-serviceable parts.

NOTES:
DANGER
1. Follow these instructions and those published by the battery
manufacturer and the manufacturer of any equipment you intend to
use in the vicinity of the battery. Review cautionary markings on these
products and on the engine.
2. This inverter/charger contains components which tend to produce
arcs or sparks.
3. Locations include any space containing gasoline-powered
machinery, fuel tanks, as well as joints, fittings, or other connections
between components of the fuel system.
FIRE AND BURN HAZARD
• Do not cover or obstruct the air intake vent openings and/or install in a
zero-clearance compartment.
• Do not use transformerless battery chargers in conjunction with the
inverter/charger due to overheating.
Failure to follow these instructions will result in death or serious injury.
DANGER
EXPLOSION HAZARD
• Charge only properly rated (such as 12 V) rechargeable batteries because
other battery types may explode.
• Do not work in the vicinity of lead-acid batteries. Batteries generate
explosive gases during normal operation. See note #1.
• Do not install and/or operate in compartments containing flammable
materials or in locations that require ignition-protected equipment. See
notes #2 and #3.
Failure to follow these instructions will result in death or serious injury.

Precautions When Working With Batteries
WARNING
5. Use extra caution to reduce the risk or dropping a metal tool on the
battery. It could spark or short circuit the battery or other electrical
parts and could cause an explosion.
6. Batteries can produce a short circuit current high enough to weld a
ring or metal bracelet or the like to the battery terminal, causing a
severe burn.
7. When removing a battery, always remove the negative terminal from
the battery first for systems with grounded negative. If it is grounded
positive, remove the positive terminal first. Make sure all loads
connected to the battery and all accessories are off so you don’t
cause an arc.
BURN FROM HIGH SHORT-CIRCUIT CURRENT, FIRE AND
EXPLOSION FROM VENTED GASES HAZARDS
• Always wear proper, non-absorbent gloves, complete eye protection,
and clothing protection. Avoid touching your eyes and wiping your
forehead while working near batteries. See note #4.
• Remove all personal metal items, like rings, bracelets, and watches
when working with batteries. See notes #5 and #6 below.
• Never smoke or allow a spark or flame near the engine or batteries.
• Never charge a frozen battery.
Failure to follow these instructions can result in death or serious injury.
NOTES:
1. Mount and place the Ultra UL1741 Inverter/Charger unit away from
batteries in a well ventilated compartment.
2. Always have someone within range of your voice or close enough to
come to your aid when you work near a lead-acid battery.
3. Always have plenty of fresh water and soap nearby in case battery acid
contacts skin, clothing, or eyes.
4. If battery acid contacts skin or clothing, wash immediately with soap and
water. If acid enters your eye, immediately flood it with running cold water
for at least twenty minutes and get medical attention immediately.

Precautions When Preparing to Charge Precautions When Placing the Inverter/Charger
NOTES:
WARNING
NOTICE
EXPOSURE TO CHEMICALS AND GASES HAZARD
• Make sure the area around the battery is well ventilated.
• Make sure the voltage of the batteries matches the output voltage of
the inverter/charger.
• Be careful to keep corrosion from coming into contact with your eyes
and skin when cleaning battery terminals.
Failure to follow these instructions can result in death or serious injury.
RISK OF DAMAGE TO THE INVERTER/CHARGER
• Never allow battery acid to drip on the inverter/charger when reading
gravity, or filling battery.
• Never place the Ultra UL1741 Inverter/Charger unit directly above
batteries; gases from a battery will corrode and damage the inverter/
charger.
• Do not place a battery on top of the inverter/charger.
Failure to follow these instructions can damage the unit and/or
damage other equipment.
• Study and follow all of the battery manufacturer's specific precautions,
such as removing or not removing cell caps while charging, whether
equalization is acceptable for your battery, and recommended rates of
charge.
• For flooded non-sealed batteries, add distilled water in each cell until
battery acid reaches the level specified by the battery manufacturer. This
helps to purge excessive gas from cells. Do not overfill. For a battery
without removable cell caps, carefully follow manufacturer's instructions.

Regulatory
The Ultra UL1741 Inverter/Charger is certified to appropriate US and
Canadian standards. For more information see “Regulatory Approvals”
on the Specifications section in the Owner’s Guide.
The Ultra UL1741 Inverter/Charger is intended to be used for mobile or
commercial applications. This inverter/charger is designed for marine
applications only when additional drip protection is installed in certain
orientations.
It is not intended for other applications as it may not comply with the
additional safety code requirements needed for those other applications.
See "Limitations On Use" below.
CAUTION
LIMITATIONS ON USE
Do not use in connection with life support systems or other medical
equipment or devices.
Failure to follow these instructions can result in death or serious injury.

Important Safety Instructions iii
Intruduction 1
General Information 1
Application 2
Key Features 2
Basic Protection Features 2
Key Features Explained 3
Multi-Stage Charger 3
Charing Current For Each Model 5
Transfer 5
Power Saver 6
Remote Control 9
Audible Alarm 10
Fan Operation 10
Battery voltage recovery start 10
Conformal Coating 10
View of Front Panel 11
AC and DC Side Panels 12
Materials List 13
Installation Information 14
Before You Begin the Installation 14
Installation Codes 14
Planing the Installation 15
Two Key Performance Factors 15
Size and Length of DC Cables 15
Mounting Location of the Ultra UL1741 15
Planing Preparations 16
AC, DC, and Network Components 16
Unpacking and Inspection the Ultra UL1741 Inverter/Charger 18
Installation Tools 18
To unpack and inspect 18
Installation Materials 18
Installation 19
Step 1: Choosing a location for the Inverter/Charger 19
Contents

Step 2: Mounting the Inverter/Charger 20
Considerations 20
To mount the Inverter/Charger 20
Step 3: Connecting the AC Input and AC Output Wires 22
General AC Wiring Considerations 22
Connecting AC Input and AC Output Wires 23
Step 4: Connecting the DC Cables 24
DC Connection Precautions 24
Recommended Cable Sizes and Lengths and Fuse Size 24
Guidelines for Routing the DC Cables 25
Connecting the DC Cables to the Inverter/Charger 25
To connect the DC Cables 26
DC Grounding 27
Step 5: Connecting the Battery Temperature Sensor (BTS) 28
Inverter/Charger Physical Specifications 29
Battery Information 30
Battery Bank Sizing 30
Estimating Battery Requirements 31
Calculating Battery Size 31
Battery Banks 32
Battery Bank Sizing Worksheet 33
Battery Cabling and Hook-up Configurations 34
Battery Parallel Connection 34
Battery Series Connection 35
Battery Series-Parallel Connections 35
Troubleshooting Guide 36
Specification 38

General Information
Introduction
Ultra UL1741 series pure sine wave inverter charger is a combination of an inverter, battery charger and AC auto-transfer switch into one complete
system with a peak DC to AC conversion efficiency of 90%. It is packed with unique features and it is one of the most advanced inverter charger in the
market today. It features power factor corrected, sophisticated multi-stage charging and pure sine wave output with unprecedenetedly high surge
capability to meet demanding power needs of inductive loads without endangering the equipment.
The powerful battery charger of this series inverter charger goes as high as 90Amps (varying on different models), and with power factor corrected, it
uses 20-30% less energy from AC input than a standard charger, avoiding nuisance breaker trips or generator overloads.
The overload capacity is 300% of continuous output for up to 20 seconds to reliably support tools and equipment longer.
The transformers have been consistently improved for years to achieve the best balance of conversion efficiency, The consumption and miminum
THD.
The idle consumption of the line is ultra low, roughly 1.5% of its rated power.
The models are available in 120Vac (single phase)
In AC priority mode, when AC power cuts off (or falls out of acceptable range), the transfer relay is de-energized and the load is automatically
transferred to the inverter output. Once the qualified AC power is restored, the relay is energized and the load is automatically reconected to AC
utility.
When customized to battery priority mode via LCD setting, the inverter will extract maximum power from external power sources in renewable
energy systems and a minimal cycle of battery will be required.
Thus the Ultra UL1741 series pure sine wave inverter charger is suitable for a myriad of applications including renewable energy systems, utility,
truck, RV and emergency vehicles etc.
To get the most out of the power inverter, it must be installed, used and maintained properly. Please read the instructions in this manual before
installing and operating.

Applications Key Features
Basic Protection Features
Power tools–circular saws, drills, grinders, sanders, buffers, weed and hedge
trimmers, air compressors.
Office equipment – computers, printers, monitors, facsimile machines,
scanners.
Household items – vacuum cleaners, fans, fluorescent and incandescent
lights, shavers, sewing machines.
Kitchen appliances – coffee makers, blenders, ice markers, toasters.
Industrial equipment – metal halide lamp, high – pressure sodium lamp.
Home entertainment electronics – television, VCRs, video games, stereos,
musical instruments, satellite equipment.
The Ultra UL1741 inverter charger is equipped with extensive protections
against various harsh situations/faults. These protections include:
When Over temperature /Over load occur, after the fault is cleared, the
master switch has to be reset to restart the inverter.
The Low batter voltage trip point can be customized from defaulted value
10VDC to 10.5VDC thru the LCD display.
The inverter will go to Over temp protection when heat sink temp. ≥105ºC,
and go to Fault (shutdown Output) after 30 seconds. The switch has to be
reset to activate the inverter.
The Prime series Inverter has back feeding protection which avoids
presenting an AC voltage on the AC input terminal in Invert mode.
After the reason for fault is cleared, the inverter has to be reset to start
working.
lAC input over voltage protection/ AC input low voltage protection
lLow batter alarm/high voltage alarm
lOver temperature protection/Over load protection
lShort circuit protection(1s after fault)
lBack feeding protection
lDesigned to operate under harsh environment
lAutomatic voltage regulator (AVR) when working in charger mode
and line mode.
lDC start & automatic self-diagnostic function
lTrue sine wave output (THD<3%) to operate sensitive electronic
and electrical equipment.
lAutomatic Generator Start Function (AGS)
lEasy to install & easy to operate & easy to solve
lLow DC voltage supports home and office appliances
lCharge rate selectable from 0%-100%
lHigh efficiency design.
l13Vdc battery recovery point, dedicated for renewable energy
systems.
l8 pre-set battery type selector plus De-sulphation for totally flat
batteries.
lPower factor corrected multi-stage charger for fast, efficient
charging, minimizing charging time.
l10ms max transfer time between utility and battery, guarantees
power continuity.
l15s delay before transfer when AC resumes, protection for load
when used with generator.
lConformal coated circuit boards for humid environments.
lBattery temperature sensoring (BTS)
lLCD and LED display to indicate the status of the inverter charger
lUL listed to UL1741 & CSA C22.2 #107.1
lSurge capacity to start difficult loads like refrigerators or A/C
compressors.
lPower save mode to reduce idle consume.

Key Features Explained
Multi-Stage Charger
Bulk Charging:
This is the initial stage of charging. While Bulk
Charging, the charger supplies the battery with controlled constant
current. The charger will remain in Bulk charge until the Absorption
charge voltage (determined by the Battery Type selection) is
achieved. Software timer will measure the time from A/C start until
the battery charger reaches 0.3V below the boost voltage, then
take this time as T0.
Absorb Charging:
This is the second charging stage and begins after
the absorb voltage has been reached. Absorb Charging provides
the batteries with a constant voltage and reduces the DC charging
current in order to maintain the absorb voltage setting. In this
period, the inverter will start a T1 timer; the charger will keep the
boost voltage in Boost CV mode until the T1 timer has run out.
Then drop the voltage down to the float voltage. The timer has a
minimum time of 30 Mins and a maximum time of 45 Mins.
Float Charging:
The third charging stage occurs at the end of the
Absorb Charging time. While Float charging, the charge voltage is
reduced to the fl oat charge voltage (determined by the Battery
Type selection*). In this stage, the batteries are kept fully charged
and ready if needed by the inverter. If the A/C is reconnected or
the battery voltage drops below 12Vdc/24Vdc, the charger will
reset the cycle above.
If the charge maintains the float state for 10 days, the charger will
deliberately reset the cycle to protect the battery.
Figure 1
Charge Mode LED will be orange during this stage
Charge Mode LED will blink orange during this stage
Charge Mode LED will be green during this stage

De-sulphation
Charging depleted batteries
Battery Type Selector Setting
The de-sulphation cycle, switch position 8, is marked in red because
this is a very dangerous setting if you do not know what you are doing.
Before attempting to use this cycle you must clearly understand what it
does and when and how you would use it. What causes sulphation?
This can occur with infrequent use of the batteries, or if the batteries
have been discharged so low that they will not accept a charge. This
cycle is a very high voltage charge cycle designed to try to break down
the sulphated crust that is preventing the plates from taking a charge
and thus allow the plates to clean up and accept a charge once again.
The Ultra UL1741 series inverter allows start up and through power with
depleted batteries.
For 12VDC models: after the battery voltage goes below 10V and the
power switch is kept in the "ON" position and the inverter stays
connected to the battery and the battery voltage doesn't drop below
2V, the inverter will be able to charge the battery once qualified AC
inputs are present. Before the battery voltage goes below 9VDC, the
charging can be activated when the switch is turned to "Off", then to
"ON".
When the voltage goes below 9VDC, and you accidently turn the switch
to OFF or disconnect the inverter from the battery, the inverter will not
be able to charge the battery once again, because the CPU loses
memory during this process.

Swift Power Transfer
1500W 12Vdc 50A
2500W 24Vdc 40A
3500W 24Vdc 50A
4500W 24Vdc 60A
3500W 48Vdc 25A
4500W 48Vdc 30A
6000W 48Vdc 55A
3500W 24Vdc 50A
4500W 24Vdc 60A
3500W 48Vdc 25A
4500W 48Vdc 30A
Synchronized Power Transfer
Transfer Delay
Charing Current For Each Model
Transfer
While in the Standby Mode, the AC input of the inverter is continually
monitored. Whenever AC power falls below the low AC voltage trip
voltage (90VAC default setting for 120VAC), the inverter automatically
transfers back to the Invert Mode with minimum power interruption to
your appliances - as long as the inverter is turned on. The transfer from
Standby mode to Inverter mode occurs in approximately 10
milliseconds. And it is even shorter from Inverter mode to Standby
mode.
This transfer time is usually fast enough to keep your equipment
(including computers) powered up, thus our inverter can be used as a
line interactive UPS.
FULAGDA3548D
FULAGDA4548D
The charging capacity will go to peak charge rate in about 3 seconds. This
may cause a generator to drop frequency, making the inverter transfer to
battery mode.
It is suggested to gradually put the charging load on the generator by
switching the charging switch from min to max. Together with the 15s
switch delay our inverter gives the generator enough time to spin up. This
will depend on the size of the generator and rate of charge.
As a general Rule, the Bulk Charging Current should be limited to 30% of
the capacity of the battery bank. Higher charging current may be used if
permitted by the battery manufacturer.
CAUTION
CAUTION: Please use a small jeweler's style flat-head screwdriver to turn
the charge current control switch gently to avoid breakage due to over-
turning.
To guarantee the best performance of AC charger when the AC input is
from a generator, the standby generator should be of at least 150% higher
capacity than the inverter.
Warning! Operation with an under-rated generator or generator with
unqualified wave form may cause premature failure which is not under
warranty.
There is a 15-second delay from the time the inverter senses that
continuously qualified AC is present at the input terminals to when the
transfer is made. This delay is built in to provide sufficient time for a
generator to spin-up to a stable voltage and frequency and avoid relay
chattering. The inverter will not transfer to generator until it has locked
onto the generator’s output. This delay is also designed to avoid
frequent switching when input utility is unstable.
When a load is transferred from inverter AC output to another backup
AC source of power through a transfer switch, there will be a finite
interruption of power to the load for the transfer to take place.
A mismatch of phase and frequency of the inverter AC output and the
backup AC source in transfer is likely to damage the backup AC source
/ a reactive load.
With sophisticated circuitry design, our inverter will first lock on the
frequency and phase of the input shore power/generator power and
make a smooth and safe transfer at the zero voltage point to minimize
the impact on the power modules.
Model
Rated
Power
Battery
Voltage
Max
Current
FULAGDA1512A/T
FULAGDA2524A/T
FULAGDA3524A/T
FULAGDA3524D
FULAGDA4524D
FULAGDA4524A/T
FULAGDA3548A
FULAGDA4548A
FULAGDA6048D

Inverter
Condition
Battery Temperature Sensor
Applying the proper charge voltage is critical for achieving optimum
battery performance and longevity. The ideal charge voltage required by
batteries changes with battery temperature.
The battery temperature sensor allows the charge controller to
continuously adjust charge voltage based on actual battery temperature.
Temperature compensation of charge voltage assures that the battery
receives the proper charge voltage as battery temperature varies.
The entire line is equipped with Battery Temperature Sensing for increased
charging precision.
It sends precise information to the charger, which automatically adjusts
voltage to help ensure full battery charge depending on the ambient
temperature of your battery installation.
When the battery voltage is over 40°C(104°F), it will reduce the charging
voltage by 0.1Vdc with every degree of temperature rise.
We recommend that you install Battery Temperature Sensors on all banks
to protect your batteries and to provide optimal charging of each bank.
The battery temperature sensor mounts on the side of a battery or any
other location where the precise temperature of battery can be detected
such as battery mounting racks.
The following table describes approximately how much the voltage may
vary depending on the temperature of the batteries.
IMPORTANT: If the battery temperature is allowed to fall to extremely
cold temperatures, the inverter with a BTS may not be able to properly
recharge cold batteries due to maximum voltage limits of the inverter.
Ensure the batteries are protected from extreme temperatures.
For more detailed technical information, please contact us.
A Battery Temperature Sensor (Part
#:ULTRAFEBTS) has been provided
as a separate accessory. It comes
with 32.8'/10m cable.
Temperature on BTS
Charger Operation
Charger
Mode
BTS≥50°C (122ºF)
Automatically turns off charger
BTS≤40°C (104ºF)
Automatically turns on charger
Inverter
Mode
40°C (104ºF)≤BTS≤40°C (104ºF)
Increases low voltage shut down
point by 0.5Vdc
BTS≥50°C (122ºF)
Over Temp Fault

Note: UL-6048D don't have this function
Acceptable input voltage range (Vac)
Nominal input voltage (Vac) 100 110 120
(A) Line low loss N/W (on battery) 75/65 84/72 92/78
(B) Line low comeback N/W(on boost) 80/70 89/77 97/83
(C) Line 2nd boost threshold (on boost) ** ** **
(D) Line 2nd boost comeback(on normal) ** ** **
(E) Line 1st boost threshold (on boost) 90 99 108
(F) Line 1stboost comeback (on normal) 93 103 112
(G) Line buck comeback (on normal) 106 118 128
(H) Line buck threshold (on buck) 110 121 132
(I) Line high comeback (on buck) 115 127 139
(J) Line high loss (on battery) 120 132 144
Automatic Voltage Regulator(AVR)
Auto Generator Start
The automatic voltage regulator function is available for the full series of
Foxpower Ultra UL1741 pure sine wave inverter charger models.Instead of
simply bypassing the input AC to power the loads, the Ultra UL1741 series
inverter stabilizes the input AC voltage to a range of 120V±10%.
The inverter can start up generator when battery voltage goes low.
When the inverter goes to low battery alarm, it can send a signal to
start a generator and turn the generator off after battery charging is
finished.
The auto gen start feature will only work with generators which have
automatic starting capability. The generator must have start and stop
controls [i.e., an electric starter and electric choke (for gasoline units)],
and the safety sensors to be able to start and stop automatically.
There is an open/close relay that will short circuit the positive and
negative cables from a generator start control. The input DC voltage
can vary, but the max current the relay can carry is 16Amp.
The Auto Generator Start terminal pins are not polarized.
In addition, these two pins can also be used as dry contacts to send out
"Low Battery Voltage" signal to an external alarm device.
AVR function
Ultra UL1741
0-160
** Only
if applicable
Figure 6
Auto
Generato r
Start

Remote Control
Apart from the switch panel on the front (or top) side of the inverter, an
extra LCD remote switch panel (Figure 7) connected to the remote port at
the DC side of the inverter through a standard Ethernet cable can also
control the operation of the inverter.
If an extra switch panel is connected to the inverter via "remote control
port", together with the panel on the inverter case, the two panels will be
connected and operated in parallel.
Whichever first switches from "Off" to "Power saver off" or "Power saver on",
it will power the inverter on.
If the commands from the two panels conflict, the inverter will operate
according to the following priority: Power saver on> Power saver off>
Power off
Only when both panels are turned to the "Unit Off" position, will the
inverter be powered off.
The Max length of the LCD remote control data cable is 60 feet (18 meters).
The LCD remote control panel will display the operation status of the
inverter, including:
• Input AC Voltage
• Output AC Voltage
• Battery Voltage
• Output Frequency
• Output Load
• Work Mode
• Alarm
• Fault
• Battery Capacity
Figure 6
Figure 7
Figure 8

Power Saver
There are two different working statuses for our Ultra UL1741 inverter:
"Power On" and "Power Off".
When the power switch on power switch panel (Figure 2) is in "Unit Off"
position, the inverter is powered off.
When the power switch is turned to either of "Power Saver Auto" or "Power
Saver Off", the inverter is powered on.
Power saver function is designed to conserve battery power when AC power
is not or rarely required by the loads.
In this mode, the inverter pulses the AC output looking for an AC load (i.e.,
electrical appliance). Whenever an AC load (greater than 50 watts) is turned
on, the inverter recognizes the need for power and automatically starts
inverting and output goes to full voltage. When there is no load (or less
than 50 watts) detected, the inverter automatically goes back into search
mode to minimize energy consumption from the battery bank.
In "Power saver on" mode, the inverter will draw power mainly in sensing
moments, thus the idle consumption is significantly reduced.
The inverter is factory defaulted to detect load for 250ms every 3 seconds.
This power sensing can be customized to "Unit off charging" via the LCD
setting. In the searching mode, the power draw to less than 25W
Figure 2
Figure 3
Figure 4
Figure 5

Condition Speed
OFF
50%
100%
OFF
50%
100%
Load % OFF
50%
100%
Battery voltage recovery start
Over Temperature
Heatsink temp.≥105ºC, Fault LED blinks and LCD
Displays "Over temp", beeps 0.5s every 1s.
After low battery voltage shut off (10V for 12V model/20V for 24V
model), the inverter is able to restore to work after the battery voltage
recovers to 13Vdc/26Vdc (with power switch still in the "On" position).
This function helps to save the users extra labor to reactivate the
inverter when the low battery voltage returns to an acceptable range in
the renewable energy systems.
Fan Operation
The Operation of the DC fan at the DC terminal side is controlled by the
following logic
Audible Alarm
Battery Voltage Low
LCD displays "BATT LOW", and the buzzer beeps
0.5s every 5s
Allow at least 30CM of clearance around the inverter for air flow. Make
sure that the air can circulate freely around the unit.
Variable speed fan operation is required in invert and charge mode.
This is to be implemented in such a way as to ensure high reliability
and safe unit and component operating temperatures in an operating
ambient temperature up to 50°C.
• Speed to be controlled in a smooth manner as a function of internal
temperature and/or current.
• Fan should not start/stop suddenly.
• Fan should run at minimum speed needed to cool unit.
• Fan noise level target <60db at a distance of 1m.
Battery Voltage High
LCD displays "BATT HIGH", and the buzzer beeps
0.5s every 1s and Fault after 60s
Inverter Mode Over-
Load
(1) 110%<load<125% (±10%), No audible alarm in
14 minutes, Deeps 0.5s every 1s in 15th minutes
and fault after 15 minutes; Fault LED on.
(2) 125%<load<150% (±10%), Beeps 0.5s every 1s
and Fault after 60s; Fault LED on.
(3) Load>150% (±10%), Beeps 0.5s every 1s and
Fault after 20s; Fault LED on
Never leave the loads unattended, some loads (like a Heater) may
cause accidents in such cases. It is better to shut everything off after
low voltage trip than to leave your load in the risk of fire.
Charger
Current
I ≤ 15%
I ≥20%
20%<I≤50%
I ≤ 15%/ I≥50%
I>50%
I≤40%
Enter condition
Leave condition
Heat sink
temperature
T≤60ºC
T>65ºC
WARNING
65ºC≤T<85ºC
T≤60ºC/T≥85ºC
T>85ºC
T≤85ºC
Load <30%
Load≥30%
Conformal Coating
INV Mode
30%≤Load<50%
Load≤20%/Load≥50%
Load≥50%
Load≤40%
The entire line of inverters has been processed with a conformal coating on the
PCB, making it water, rust, and dust resistant. While these units are designed to
withstand corrosion from the salty air, they are not splash proof.