OutBack Power FX Mobile Series User manual

FX Inverter/Charger
FX and VFX Mobile Series
O
p
erator’s Manual

About OutBack Power Technologies
OutBack Power Technologies is a leader in advanced energy conversion technology. OutBack products include true sine wave
inverter/chargers, maximum power point tracking charge controllers, and system communication components, as well as circuit
breakers, batteries, accessories, and assembled systems.
Applicability
These instructions apply to OutBack inverter/charger models FX2012MT, '9.FX2524MT, FX2532MT, FX2536MT, FX3048MT,
VFX2812M, VFX3524M, VFX3232M, VFX3236M, and VFX3648M only.
Contact Information
Address: Corporate Headquarters
17825 – 59th Avenue N.E.
Suite B
Arlington, WA 98223 USA
European Office
Hansastrasse 8
D-91126
Schwabach, Germany
Telephone: [phone]
+1.360.618.4363 (Technical Support)
+1.360.435.6019 (Fax)
+49.9122.79889.0
+49.9122.79889.21 (Fax)
Email: [email protected]
Website: http://www.outbackpower.com
Disclaimer
UNLESS SPECIFICALLY AGREED TO IN WRITING, OUTBACK POWER TECHNOLOGIES:
(a) MAKES NO WARRANTY AS TO THE ACCURACY, SUFFICIENCY OR SUITABILITY OF ANY TECHNICAL OR OTHER INFORMATION
PROVIDED IN ITS MANUALS OR OTHER DOCUMENTATION.
(b) ASSUMES NO RESPONSIBILITY OR LIABILITY FOR LOSS OR DAMAGE, WHETHER DIRECT, INDIRECT, CONSEQUENTIAL OR
INCIDENTAL, WHICH MIGHT ARISE OUT OF THE USE OF SUCH INFORMATION. THE USE OF ANY SUCH INFORMATION WILL BE
ENTIRELY AT THE USER’S RISK.
OutBack Power Technologies cannot be responsible for system failure, damages, or injury resulting from improper installation of
their products.
Information included in this manual is subject to change without notice.
Notice of Copyright
FX and VFX Mobile Series Inverter/Charger Operator’s Manual © 2016 by OutBack Power Technologies. All Rights Reserved.
Trademarks
OutBack Power, the OutBack Power logo, FLEXware, and OPTICS RE are trademarks owned and used by OutBack Power
Technologies, Inc. The ALPHA logo and the phrase “member of the Alpha Group” are trademarks owned and used by Alpha
Technologies Inc. These trademarks may be registered in the United States and other countries.
Date and Revision
August 2016, Revision A
Part Number
900-0198-01-00 Rev A

900-0198-01-00 Rev A 3
Table of Contents
Introduction ............................................................................................................... 7
Audience .........................................................................................................................................................................................7
Symbols Used ................................................................................................................................................................................7
Welcome to OutBack Power Technologies.........................................................................................................................8
Inverter Functions........................................................................................................................................................................8
General Safety ...............................................................................................................................................................................9
Inverter Controls...........................................................................................................................................................................9
System Display and Controller .............................................................................................................................................................9
On/Off Switch.......................................................................................................................................................................................... 10
Operation.................................................................................................................11
LED Indicators............................................................................................................................................................................. 11
Battery Indicators................................................................................................................................................................................... 11
Status Indicators..................................................................................................................................................................................... 12
Inverter Functionality .............................................................................................................................................................. 12
AC Input Connection ............................................................................................................................................................... 13
Description of Inverter Operations ..................................................................................................................................... 13
Inverting.................................................................................................................................................................................................... 13
DC and AC Voltages ....................................................................................................................................................................................................14
Search...............................................................................................................................................................................................................................14
Input........................................................................................................................................................................................................... 15
AC Current Settings.....................................................................................................................................................................................................16
AC Source Acceptance ...............................................................................................................................................................................................16
Generator Input ............................................................................................................................................................................................................17
Transfer ............................................................................................................................................................................................................................17
Battery Charging .................................................................................................................................................................................... 18
Charge Current..............................................................................................................................................................................................................18
Charge Cycle ..................................................................................................................................................................................................................19
Charging Steps..............................................................................................................................................................................................................20
New Charging Cycle....................................................................................................................................................................................................22
Equalization....................................................................................................................................................................................................................23
Battery Temperature Compensation....................................................................................................................................................................23
Multiple-Inverter Installations (Stacking)....................................................................................................................................... 25
Stacking Configurations ...................................................................................................................................................................... 26
Classic Series Stacking (Dual-Stack) ......................................................................................................................................................................26
OutBack Series Stacking (Dual-Stack)...................................................................................................................................................................26
Parallel Stacking (Dual-Stack and Larger) ...........................................................................................................................................................27
Series/Parallel Stacking (Quad-Stack or Larger)................................................................................................................................................28
Three-Phase Stacking .................................................................................................................................................................................................28
Power Save .....................................................................................................................................................................................................................29
Auxiliary Terminals ................................................................................................................................................................................ 32
System Display-Based Functions (AGS)............................................................................................................................. 34
Metering ..................................................................................................................35
MATE3 Screens........................................................................................................................................................................... 35
Inverter Screen........................................................................................................................................................................................ 35
Battery Screen ......................................................................................................................................................................................... 36

Table of Contents
4 900-0198-01-00 Rev A
Troubleshooting ....................................................................................................... 37
Basic Troubleshooting............................................................................................................................................................. 37
Error Messages ........................................................................................................................................................................... 40
Warning Messages.................................................................................................................................................................... 41
Disconnect Messages .............................................................................................................................................................. 42
Specifications ........................................................................................................... 43
Electrical Specifications........................................................................................................................................................... 43
Mechanical Specifications...................................................................................................................................................... 46
Environmental Specifications............................................................................................................................................... 46
Regulatory Specifications....................................................................................................................................................... 47
Listings .......................................................................................................................................................................................................47
Summary of Operating Limits............................................................................................................................................... 47
Default Settings and Ranges (MATE or MATE2) ............................................................................................................. 48
Default Settings and Ranges (MATE3) ............................................................................................................................... 53
Definitions.................................................................................................................................................................................... 58
Index........................................................................................................................ 59

Table of Contents
900-0198-01-00 Rev A 5
List of Tables
Table 1Battery Indicator Values.............................................................................................................................. 11
Table 2Charge Currents for FX and VFX Mobile Models ............................................................................... 18
Table 3Temperature Compensation..................................................................................................................... 24
Table 4Aux Mode Functions.................................................................................................................................... 34
Table 5Troubleshooting............................................................................................................................................ 37
Table 6Error Troubleshooting................................................................................................................................. 40
Table 7Warning Troubleshooting.......................................................................................................................... 41
Table 8Disconnect Troubleshooting .................................................................................................................... 42
Table 9Electrical Specifications for 12-Volt Mobile Models.......................................................................... 43
Table 10Electrical Specifications for 24-Volt Mobile Models.......................................................................... 43
Table 11Electrical Specifications for 32-Volt Mobile Models.......................................................................... 44
Table 12Electrical Specifications for 36-Volt Mobile Models.......................................................................... 45
Table 13Electrical Specifications for 48-Volt Mobile Models.......................................................................... 45
Table 14Mechanical Specifications for Mobile Models .................................................................................... 46
Table 15Environmental Specifications for Mobile Models ............................................................................. 46
Table 16Operating Limits for Mobile Models ...................................................................................................... 47
Table 1712-Volt Inverter Settings (MATE) ............................................................................................................. 48
Table 1824-Volt Inverter Settings (MATE) ............................................................................................................. 49
Table 1932-Volt Inverter Settings (MATE) ............................................................................................................. 50
Table 2036-Volt Inverter Settings (MATE) ............................................................................................................. 51
Table 2148-Volt Inverter Settings (MATE) ............................................................................................................. 52
Table 2212-Volt Inverter Settings (MATE3)........................................................................................................... 53
Table 2324-Volt Inverter Settings (MATE3)........................................................................................................... 54
Table 2432-Volt Inverter Settings (MATE3)........................................................................................................... 55
Table 2536-Volt Inverter Settings (MATE3)........................................................................................................... 56
Table 2648-Volt Inverter Settings (MATE3)........................................................................................................... 57
Table 27Terms and Definitions ................................................................................................................................. 58

Table of Contents
6 900-0198-01-00 Rev A
List of Figures
Figure 1FX Mobile Series Inverter/Charger with Turbo Fan .............................................................................8
Figure 2MATE, MATE2, MATE3, and AXS Port ........................................................................................................9
Figure 3LED Indicators ................................................................................................................................................ 11
Figure 4Inverter Status LED Indicators .................................................................................................................. 12
Figure 5Charging Stages (Auto Setting) ............................................................................................................... 19
Figure 6Charging Stages (On Setting)................................................................................................................... 20
Figure 7OutBack HUB10.3, MATE, MATE2 , and MATE3 .................................................................................. 25
Figure 8Example of Classic Series Stacking Arrangement ............................................................................. 26
Figure 9Example of OutBack Series Stacking Arrangement.......................................................................... 27
Figure 10Example of Parallel Stacking Arrangement (Three Inverters) ....................................................... 27
Figure 11Example of Series/Parallel Stacking Arrangement (Four Inverters)............................................ 28
Figure 12Example of Three-Phase Stacking Arrangement (Three Inverters)............................................. 28
Figure 13Power Save Levels and Loads................................................................................................................... 29
Figure 14Power Save Priority (Parallel).................................................................................................................... 30
Figure 15Power Save Priority (Split-Phase) ............................................................................................................ 31
Figure 16Home Screen .................................................................................................................................................. 35
Figure 17Inverter Screens............................................................................................................................................. 35
Figure 18Battery Screen ................................................................................................................................................ 36
Figure 19AC Test Points................................................................................................................................................. 37

900-0198-01-00 Rev A 7
Introduction
Audience
This manual provides instructions for setup and operation of the product. It does not cover installation.
The manual is intended to be used by anyone required to operate the FX or VFX Mobile Series
Inverter/Charger. Operators must be familiar with all the safety regulations pertaining to operating power
equipment of this type as required by local code. Operators are advised to have basic electrical
knowledge and a complete understanding of this equipment’s features and functions. Do not use this
product unless it has been installed by a qualified installer in accordance with the FX and VX Mobile Series
Inverter/Charger Installation Manual.
Symbols Used
WARNING: Hazard to Human Life
This type of notation indicates that the hazard could be harmful to human life.
CAUTION: Hazard to Equipment
This type of notation indicates that the hazard may cause damage to the equipment.
IMPORTANT:
This type of notation indicates that the information provided is important to the
installation, operation and/or maintenance of the equipment. Failure to follow the
recommendations in such a notation could result in voiding the equipment warranty.
NOTE:
This type of notation indicates that the information provided is important to
understanding the operation and limits of the equipment. Failure to follow the
recommendations in such a notation could result in improper or failed operation.
MORE INFORMATION
When this symbol appears next to text, it means that more information is available in other manuals relating
to the subject. The most common reference is to the FX and VFX Mobile Series Inverter/Charger Installation
Manual. Another common reference is the system display manual.

Introduction
8 900-0198-01-00 Rev A
Welcome to OutBack Power Technologies
Thank you for purchasing the OutBack FX and VFX Mobile Series Inverter/Chargers. These products are
designed to offer a complete power conversion system between batteries, shore power, and generator.
In shore-based mobile and marine connections, the shore power (utility grid) is used as the primary
source. When the shore power is removed, the inverter takes over to run the loads from the batteries.
Figure 1 FX Mobile Series Inverter/Charger with Turbo Fan
Inverter Functions
Battery (DC)-to-AC inverting which delivers single-phase power (120 Vac/60 Hz)
Rapid transfer between AC source and inverter output with minimal delay time
Wattages from 2.0 kVA to 3.6 kVA
12-, 24-, 32-, 36-, and 48-volt models
Uses the MATE, MATE2 or MATE3 System Display and Controller or the AXS Port™ SunSpec Modbus Interface
(sold separately) for user interface
MATE3 must have firmware revision 003.007.xxx or higher
Supports the OPTICS RE™ online tool1for a cloud-based remote monitoring and control application
Requires the MATE3 or the AXS Port
Visit www.outbackpower.com to download the software
Uses the HUB4™ or HUB10.3™ Communications Manager for stacking
Stackable in series (OutBack or Classic), parallel, series/parallel, and three phase configurations
Automatic neutral-to-ground bond switching
Listed to ANSI/UL 458 (5th Edition) and CSA C22.2 by ETL
Single AC input with dual input programming; individualized priorities can be selected when switching from
shore power to AC generator
external switching device required
system display required for individual programming
1Outback Power Technologies Intuitive Control System for Renewable Energy

Introduction
900-0198-01-00 Rev A 9
General Safety
WARNING: Limitations on Use
This equipment is NOT intended for use with life support equipment or other medical
equipment or devices.
WARNING: Reduced Protection
If this product is used in a manner not specified by FX product literature, the product’s
internal safety protection may be impaired.
CAUTION: Equipment Damage
Only use components or accessories recommended or sold by OutBack Power
Technologies or its authorized agents.
Inverter Controls
The FX inverter has no external controls. It can operate normally without an external control or
interface. Basic modes and settings are pre-programmed at the factory. (See the menu tables
beginning on page 48.) However, external communication devices such as the OutBack MATE3
can be used to operate, program, or troubleshoot the inverter.
System Display and Controller
Figure 2MATE, MATE2, MATE3, and AXS Port
The MATE, MATE2, and MATE3 System Display and Controller and the AXS Port SunSpec Modbus Interface
(all sold separately) are designed to accommodate programming and monitoring of an OutBack inverter
system. A system display such as the MATE provides the means to adjust the default settings to match the
installation where needed, monitor system performance, and troubleshoot fault or shutdown conditions.
It also has data logging and interface functions using the Internet.

Introduction
10 900-0198-01-00 Rev A
The MATE2 is a system display designed for use with mobile FX inverters. It is intended to be
flush-mounted in a panel. Along with programmed criteria for accepting shore or generator AC sources,
it has the Advanced Generator Start function which sets many parameters for generator control.
The MATE3 is an advanced system display. In addition to the functions of the MATE2, it has improved
accessibility to screens and readings. The programming items and settings have multiple
password-protected access levels for increased security. It is intended to be surface-mounted.
NOTE:
Most references to screens, navigation, and menu items in this book are to the MATE3.
However, the tables of factory defaults and ranges at the back of the book are shown in
MATE or MATE2 format. These begin with Table 17 on page 48.
The MATE3’s Configuration Wizard is capable of automatically configuring inverters to a series of preset
values. This is often more efficient than attempting to manually program each setting in each inverter.
Affected fields include system type, battery charging, and AC source configuration.
Once settings are modified using any system display, it can be removed from the installation. The settings
are stored in the nonvolatile memory of the FX inverter. However, it is highly recommended to install it as
part of the system. This provides the means to monitor system performance and respond quickly should it
be necessary to correct a fault or shutdown condition.
The AXS Port can perform similar functions using a computer interface.
IMPORTANT:
Some functions are not based in the inverter, but are part of the system display.
They will not function if the system display is removed. These functions are listed
beginning on page 34.
IMPORTANT:
The FX inverter can use the OPTICS RE online tool as a system display. OPTICS RE must
be used in conjunction with the MATE3 or with the AXS Port SunSpec Modbus Interface.
The MATE3 system display must have firmware revision 003.000.xxx or higher.
On/Off Switch
If a system display is not in use, the inverter can be equipped with a switch to turn it on and off. This
switch is not sold as an inverter accessory; a common toggle switch can be used. The switch is wired to
the INVERTER ON/OFF auxiliary terminals. (See the FX Mobile Series Inverter/Charger Installation Manual
for more information on wiring the switch.)
This switch turns only the inverter on and off. It does not turn the charger or any other function on or off.
All inverter functions will operate according to their programmed settings. Functions included with a
system display will not be available.

900-0198-01-00 Rev A 11
Operation
LED Indicators
Figure 3 LED Indicators
Battery Indicators
The Battery LED indicators show the approximate battery state. (See IMPORTANT note below.) The Battery
indicators and the Inverter Status indicators are independent. They may accompany each other depending
on conditions. Common combinations are noted on page 12.
A green indicator (FULL) means the batteries have an adequate charge at that time. It does not always mean they
are full. It may be accompanied by a yellow Status indicator when an AC source is charging.
A yellow indicator (OK) means the batteries are somewhat discharged.
A red indicator (LOW) means the batteries are greatly discharged and may require attention. It may be
accompanied by a red Status indicator to indicate a low battery error.
Table 1 Battery Indicator Values
Color 12 Vdc Unit
24 Vdc Unit,
± 0.2 Vdc
32 Vdc Unit,
± 0.3 Vdc
36 Vdc Unit,
± 0.3 Vdc
48 Vdc Unit,
± 0.4 Vdc Battery Status
GREEN 12.5 Vdc or higher 25.0 Vdc or higher 33.3 Vdc or higher 37.5 Vdc or higher 50.0 Vdc or higher ACCEPTABLE
YELLOW 11.5 to 12.4 Vdc 23.0 to 24.8 Vdc 30.6 to 33.0 Vdc 34.5 to 37.2 Vdc 46.0 to 49.6 Vdc MARGINAL
RED 11.4 Vdc or lower 22.8 Vdc or lower 30.4 Vdc or lower 34.2 Vdc or lower 45.6 Vdc or lower LOW
NOTES:
Gaps in the table (higher-voltage units) are due to the resolution of the inverter’s DC meter.
These voltage settings are not the same as the Low Battery Cut-Out (LBCO) set point. (See page 13.) The Battery indicator
settings cannot be changed.
Voltages higher than shown in the GREEN row usually show that the batteries are charging.
IMPORTANT:
Due to different system states, battery voltage does not always indicate an accurate state of charge. It is
accurate if batteries have been at rest for several hours at room temperature (25°C or 77°F, or as specified
by the battery manufacturer). If they have any loads, a charging source, or are at another temperature,
their voltage may not reflect their true state. The OutBack FLEXnet DC is a battery monitor that can be
added to the system to provide accurate measurements.
Status Indicators
Battery
Indicators
AUX Indicator (see page 31)

Operation
12 900-0198-01-00 Rev A
Status Indicators
Figure 4 Inverter Status LED Indicators
Inverter Functionality
FX inverters possess a set of common functions or operations. These operations are described in detail
beginning on page 13.
Most of the inverter’s individual operations and functions can be programmed using the system display.
This allows customization or fine tuning of the inverter’s performance.
1
2
3
STATUS INVERTER (Green):
Solid
: The FX inverter is on and providing power.
Flashing
: The inverter has been turned on but is idle.

The inverter is likely in Search mode. See page 14.
Off
: The inverter is off. It is not waiting to provide power.

See the system display manual to turn the inverter on.

Any power present is from another source such as the utility grid
or generator.

The inverter may also be a slave that is in Silent mode due to the
Power Save function. If so, the master inverter may still be
providing power to the system.
See page 28 for a description of Power Save.
AC IN (Yellow):
Solid:
The AC source is connected and providing power.

The FX inverter may or may not be charging the batteries, depending on settings.

May be accompanied by green STATUS INVERTER indicator (1).
Flashing
: The AC source is present but has not been accepted.

If flashing continues, the FX inverter is refusing the source. See the Troubleshooting section on page 37.
Off
: No AC source is detected.

If a source is supposed to be present, see the Troubleshooting section on page 37.
ERROR (Red):
Solid
: Error. The inverter has shut down due to a critical problem which may be internal or external.

This indicator is accompanied by an error message in the system display.

See page 40 for a description of error messages.
Flashing
: Warning. The inverter has detected a non-critical problem but has not yet shut down.

A warning does not always lead to a shutdown — if it does, it becomes an error.

This indicator is accompanied by a warning message in the system display.

See page 41 for a description of warning messages.
Off
: No problems are detected.

Operation
900-0198-01-00 Rev A 13
Each distinct mode, function, or operation is accompanied by a symbol representing the inverter and
that operation:
The symbols may have other features depending on the operation.
AC Input Connection
The FX inverter has one set of input connections. Only one AC source can be physically wired to it at any
time. However, two different AC sources (usually shore power and generator) can be used with an
external transfer switch. The inverter can be programmed with separate input criteria for each source.
See the FX Mobile Series Installation Manual for more information on connections.
The inverter’s two input selections can be programmed for separate input modes (see below). The
selection (Grid or Gen) can be chosen in the AC Input and Current Limit menu. (See the MATE3 menu
tables beginning on page 53.)
NOTE:
The input types are labeled for grid and generator due to common conventions, not
because of inverter requirements. Each selection can accept any AC source as long as it
meets the requirements of the FX inverter and the selected input mode. If necessary,
the Gen selection can accept grid power. The opposite is also true.
Description of Inverter Operations
The items in this section are operations common to all FX inverters. These are used in most or all of the
input modes described in the preceding section.
Some of the items in this section are functions which can be manually selected, enabled, or customized.
Other items are general topics or applications for the inverter. These items may not have their own
menus, but their activity can still be influenced or optimized by changing certain settings.
Any of these items may need to be adjusted so that the inverter is best matched to a particular
application. The operator should review these items to see which are applicable.
All items described as settable or adjustable have set points which can be accessed using the
system display. The default settings and ranges of adjustment are listed in the MATE3 menu tables which
begin on page 53 of this manual.
Inverting
This is the FX inverter’s primary task. The inverter converts DC voltage from batteries into AC voltage that
is usable by AC appliances or devices. It will continue to do this as long as the batteries have sufficient
energy. The batteries can be supplied or recharged from other sources, such as PV or alternator power.
The inverter’s design uses a transformer and a high-frequency H-Bridge FET module to achieve the
required high-wattage AC output. The inverter can deliver the rated wattage continuously at 25°C. The
maximum output is derated at temperatures exceeding 25°C. See page 43 for these wattages.
Measure the total load wattage so that it does not exceed the inverter’s capacity. The inverter cannot
maintain its AC voltage under an excessive load. It will shut down with a Low Output Voltage error.
AC IN AC OUT
DC
TRANSFER
These items represent the input from the AC
source, the output to the AC loads, DC functions
(inverting, charging, etc.), and the transfer relay.
Arrows on each symbol represent power flow.

Operation
14 900-0198-01-00 Rev A
DC and AC Voltages
The FX inverter requires batteries to operate. Other sources may not maintain DC voltages that are
consistent enough for the inverter to operate reliably.
CAUTION: Equipment Damage
Do not substitute other DC sources in place of the batteries. High or irregular voltages
may damage the inverter. It is normal to use other DC sources with the batteries and
the inverter, but not in place of the batteries.
The following items will affect the inverter’s operation. These are only used when the inverter is
generating AC power on its own.
Low Battery Cut-Out: This function prevents the inverter from draining the batteries completely. When the DC
voltage drops below a specified level for 5 minutes, the inverter will stop functioning. The MATE3 will give a Low
Battery V error. This is one of the error messages described on page 40. It appears as an event on the MATE3
system display.
This function is intended to protect both the batteries and the inverter’s output. (Continuing to invert on a low
DC voltage may produce a distorted waveform.) This item is adjustable.
Low Battery Cut-In: The recovery point from Low Battery Cut-Out. When the DC voltage rises above this point
for 10 minutes, the error will clear and the inverter will resume functioning. This item is adjustable.
Connecting an AC source for the inverter to charge the batteries will also clear a low battery error.
Output Voltage: The AC output voltage can be adjusted within a limited range.
NOTE:
The inverter’s output frequency is 60 Hz. This is not adjustable.
The inverter is also controlled by a high battery cut-out limit. If the DC voltage rises above this limit, the inverter
immediately stops functioning and gives a High Battery V error. The shutdown protects the inverter from
damage due to excessive DC voltage.
The high battery cut-out voltages for each model are shown in Table 16 on page 47. This voltage is not a changeable
set point.
If the voltage drops below this point, the inverter automatically recovers.
This is one of the errors on page 40. It appears as an event on the MATE3 system display.
The low battery and high battery functions are summarized in Table 16 on page 47.
Search
An automated search circuit is available to minimize the power draw when no loads are present. When
enabled, the inverter does not always deliver full output. The output is reduced to brief pulses with a
delay between them. These pulses are sent down the output lines to see if a resistance is present.
Basically, the pulses “search” for a load. If a load is detected on the output, the inverter’s output increases
to full voltage so that it can power the load. When the load is turned off, the inverter “goes to sleep” and
begins searching again.
Search mode sensitivity is adjusted with the Sensitivity menu item. See the menu tables, which begin on
page 53, for the location of this item. The sensitivity is adjusted in small increments which are measured
in fractions of one ampere.
V
V

Operation
900-0198-01-00 Rev A 15
NOTE:
Increment sizes are difficult to define due to varying load characteristics. However, the
default setting, 6 increments, is approximately sufficient to detect the load of one
compact fluorescent light (CFL). A load which draws this amount or greater will “wake
up” the inverter.
Search mode is not particularly useful with loads requiring continuous power. (These loads include clocks,
answering machines, and similar devices.) “Sleep” operation with these loads is simply a power interruption or
nuisance shutdown.
Search mode may not be useful with loads that are critical or are intentionally operated a large portion of the
time even if they are not continuous. (These loads include computers and similar devices.) The inverter may
“sleep” so rarely that the mode has no benefit.
Some devices may not be easily detected by Search mode.
Search mode is ideal for use in small systems where it is critical to conserve battery capacity and avoid idle
draw or “ghost” loads.
To set up Search mode for use:
1. Turn off all loads.
2. Activate Search mode with the system display. The inverter should “sleep” with a flashing green STATUS
INVERTER indicator. See page 12.
3. Determine the smallest load that is to be used and turn it on.
4. If the load operates, the inverter is active and is producing power. No further adjustments are needed.
5. If the inverter does not produce power and continues to “sleep”, the sensitivity is set too high. Turn the load off
and lower the Sensitivity menu item. Turn on the load and test whether the inverter activates.
6. Repeat step 5 as needed until turning on the load also reliably activates the inverter.
The pulse duration and the delay both have a time period that is measured in AC cycles. These two items,
Pulse Length and Pulse Spacing, are adjustable in the same menu as Sensitivity. If Sensitivity does not
achieve the desired results, it may be useful to perform similar adjustments on these items.
Input
When the input terminals are connected to a stable AC source, the FX inverter will synchronize itself with
that source and use it as the primary source of AC power. Its transfer relay will engage, linking the AC
source directly with the inverter’s output. It can also use the source to charge batteries. (See Battery
Charging on page 18.)
The loads powered by the inverter must not exceed the size of the inverter’s transfer relay.
CAUTION: Equipment Damage
Current draw in excess of the transfer relay rating can damage the transfer relay. This
damage is not covered by warranty. Use protective devices of appropriate size.
The inverter has a single AC input. However, it has two sets of AC source settings. With an external transfer
switch, the inverter can be used on more than one AC source. It is common to use shore (utility grid) power and a
generator. Other combinations are possible.

Operation
16 900-0198-01-00 Rev A
AC Current Settings
The AC current settings, Grid Input AC Limit and Gen Input AC Limit, control the amount of current that
the inverter draws from the source. Adjust these settings to match the input circuit breakers.
The adjustment is meant to protect a generator or shore supply that cannot supply enough current for both
charging and loads. If the combined charging and loads exceed the setting, the inverter will reduce its charge
rate and give priority to the loads. If the loads exceed this number on their own, the charge rate will be reduced
to zero.
The inverter’s battery charger has individual settings. However, the AC Limit settings can also limit the charging
or selling current.
The AC input current is used to power both loads and battery charging. The combined amount should not
exceed the size of the AC overcurrent device or AC source. These devices should be sized appropriately during
planning and installation of the inverter system.
If multiple parallel inverters are installed with an AC source of limited amperage, the total combined amperage
settings for all units must be less than the AC input circuit. The MATE3 Configuration Wizard can perform this
calculation. However, the inverters do not perform this calculation. If the Wizard or similar tools are not used,
divide the input size by the number of inverters and assign an equal part of the amperage to each port.
AC Source Acceptance
The input source must meet the following specifications to be accepted.
Voltage: 108 to 140 Vac
Frequency: 54 to 66 Hz
See the menu tables which begin on page 48 for voltage programming information.
When these conditions are met, the inverter will close its transfer relay and accept the input source. This
occurs after a delay which is specified below. If the conditions are not met, the inverter will not accept the
source. If it was previously accepted and then rejected, the inverter will open the relay and return to
inverting power from the batteries. This occurs after a specified transfer delay, which is an adjustable
menu item.
The voltage limits can be adjusted to allow (or exclude) a source with weak or irregular voltages.
These items are adjustable in the appropriate menu of the MATE3 (Grid AC Input Mode and Limits or
Gen AC Input Mode and Limits). The settings are titled Voltage Limit Lower and Upper. There can be side
effects to changing the range of allowed voltages.
Each of the AC input selections has a settable Connect Delay. This is intended as a warmup period which allows
an input source to stabilize before connection.
The default setting for the Grid selection is 0.2 minutes (12 seconds).
The default setting for the Gen selection is 0.5 minutes (30 seconds).
These items are adjustable in the appropriate menu of the MATE3 (Grid AC Input Mode and Limits or Gen AC Input
Mode and Limits).
NOTE:
Several items external to the inverter may prevent the inverter from accepting AC
power even if electrical conditions are met. An example is the MATE3’s AC INPUT hot
key menu, which can disconnect all inverters when set to Drop.
A
A
A

Operation
900-0198-01-00 Rev A 17
Multiple Inverters
In a stacked system, whenever the master inverter senses acceptable input, it orders all other inverters to
transfer to the AC source. The other inverters do not use their own input readings to transfer. It is
expected that the AC source delivers input (in the appropriate phase) to all inverters.

If a slave inverter does not sense acceptable input, it will not transfer, but also will not invert. The slave will have
no output. It also will display Phase Loss Error.
Generator Input
A generator should be sized to provide enough power for all inverters, both for loads and for battery
charging. The generator’s voltage and frequency must match the inverter’s acceptance settings.
It is usually recommended that the generator be sized at twice the wattage of the inverter system. Many
generators may not be able to maintain AC voltage or frequency for long periods of time if they are loaded
more than 80% of rated capacity.
The generator is required to have a stable output before its power is accepted by the inverter. Some
generators with less stable or uneven outputs may not be accepted. The use of the Generator input
mode may assist with this problem.
Transfer
The FX inverter uses a transfer relay to alternate between the states of inverting and of accepting an AC
source. Until the relay energizes, the output terminals are electrically isolated from the input. When it
closes, the input and output terminals become electrically common. When the relay changes states, the
physical transfer delay is approximately 25 milliseconds.
CAUTION: Equipment Damage
Current draw in excess of the transfer relay rating can damage the transfer relay. This
damage is not covered by warranty. Use protective devices of appropriate size.
The relay contacts are limited to 30 amps per phase. The continuous loads on that output should never
exceed this number. When connected to an AC source, the FX inverter cannot limit the load current. An
overload condition is possible.
The inverter does not filter or actively condition the AC source. The voltage and power quality received by
the output loads is the same as that of the source. If the voltage or quality do not meet the inverter’s input
requirements, it will disconnect and return to the inverting mode.
NOTES:

To ensure a smoother transition, it may be advisable to raise the inverter’s lower acceptance limit. The default
setting is 108 Vac. A higher setting will cause the inverter to transfer sooner in the event of a quality problem.
If the AC source meets the inverter’s requirements but is irregular, any fluctuations will be transferred to the
loads. If the loads are sensitive, it may be necessary to improve the quality of the AC source.
If the charging function is turned off, the inverter will transfer power from the source but will not use it to
charge. If the inverting function is turned off, the inverter will transfer (“pass through”) the source power
when connected, but will not invert when the source is removed.

Operation
18 900-0198-01-00 Rev A
Battery Charging
IMPORTANT:
Battery charger settings need to be correct for a given battery type. Always follow battery
manufacturer recommendations. Making incorrect settings, or leaving them at factory default
settings, may cause the batteries to be undercharged or overcharged.
Charge Current
Batteries or battery banks usually have a recommended limit on the maximum current used for charging.
Often this is calculated as a percentage or fraction of the battery capacity, represented by “C”. For
example, C/5 would be a DC amperage figure that is 1/5 of the total amp-hours of the bank.
Any chargers must be set so that the peak charge current does not exceed the recommended battery
maximum. If multiple chargers are present (including other types of chargers besides the inverter), this
calculation must accommodate the total combined current. The FX charger may need to be set at less
than maximum. The system display can be used to change charger settings.
IMPORTANT:
Although the recommended current is generally represented in DC amperes (Adc), the Charger
AC Limit setting is measured in AC amperes (Aac), which use a different scale. To convert the
DC current into a usable AC figure, divide the DC figure by the following number (based on
inverter voltage) and round up. The result can be used as a charger setting for the FX inverter.
12-volt inverters: Divide by 10
24-volt inverters: Divide by 5
32-volt inverters: Divide by 3.33
36-volt inverters: Divide by 3.75
48-volt inverters: Divide by 2.5
Examples:
1) Bank consists of 8 x L16 FLA batteries in series for a 48-volt system. Recommended
maximum charge current is 75 Adc. (75 ÷ 2.5 = 30 Aac)
2) Bank consists of 6 x OutBack EnergyCell 200RE VRLA batteries in series/parallel for a 24-volt
system. Recommended maximum charge current is 45 Adc. (45 ÷ 5 = 9 Aac)
The maximum DC charge rate for FX models is specified in Table 9 on page 43. The actual Charger
AC Limit setting is available in the AC Input and Current Limit menu of the MATE3 system display.
(See the menu tables which begin on page 53.) These numbers are also summarized in Table 2.
NOTE: This table does not match the calculations above due to other factors in charging.
Table 2 Charge Currents for FX and VFX Mobile Models
Model Maximum DC Output (sent to battery) Maximum AC Input (used from source)
FX2012MT 80 Adc 12 Aac
FX2024M 40 Adc 12 Aac
FX2524MT 55 Adc 14 Aac
FX2532MT 35 Adc 14 Aac
FX2536MT 35 Adc 14 Aac
FX3048MT 35 Adc 14 Aac
VFX2812M 125 Adc 16 Aac
VFX3524M 82 Adc 20 Aac
VFX3232M 45 Adc 20 Aac
VFX3236M 45 Adc 20 Aac
VFX3648M 45 Adc 20 Aac

Operation
900-0198-01-00 Rev A 19
Charge Current for Multiple Inverters
If FX inverters are stacked, the master inverter Charger AC Limit setting is used by all other inverters.
Divide the total AC current by the number of chargers used and program the master with the result. The
master will operate all chargers with this setting to achieve the maximum total charge current. The
system display has a global Charger Control command of On which enables all available chargers.
Limiting Charge Current (Multiple Inverters)
It is not advisable to set Charger AC Limit less than 12 Aac in a stacked system. The Power Save function
requires the master to activates the slave chargers in sequence only when the charge current exceeds
11 Aac. If the setting is less than 12, Power Save will not activate any other chargers.
For more information on this function, see the Power Save section beginning on page 28.
Charge Cycle
FX and VFX mobile inverters use a “three-stage” battery charging process with Bulk, Absorption, and Float
stages. These stages follow a series of steps which are shown on graphs and described beginning below.
The inverter’s factory default settings are intended for three-stage charging of lead-acid batteries.
Charging Graphs
When the charger is set to <Auto> using the system display, the charger automatically progresses
through a three-stage cycle. Upon completion, the charger switches between Float stage and Silent mode
as described on page 21. This is often selected to maintain batteries from shore power.
Figure 5 shows the progression of steps of the <Auto> charging cycle.
Figure 5 Charging Stages (Auto Setting)
When the charger is set to <On> using the system display, the charger automatically progresses through a
three-stage cycle. However, this setting eliminates the Silent and Refloat steps. The charger remains in
Float continuously. The Float stage lasts until the AC source is removed. This is often selected when
charging from an automatic generator which shuts down at the Float stage.
Figure 6 on the next page shows the progression of steps of the <On> charging cycle.
Voltage
Time
Inverter now charging to a new set point Inverter has reached the charging set point
Inverter completed charging; the previous set point is no longer in use
Bulk ReFloat
Absorption FloatSilent
Absorption
Set Point
Float
Set Point
Re-Float
Set Point
No Charge Silent ReFloat Float Silent Refloat

Operation
20 900-0198-01-00 Rev A
Figure 6 Charging Stages (On Setting)
Charging Steps
The following items describe the operation and intended use for each individual charging step as shown
in the graphs. Note that some charging cycles may not follow this exact sequence, including cycles which
were previously interrupted.
See page 22 for a description of multiple cycles when the charger is restarted after completion. This page
also describes multiple cycles when the charger is restarted after being interrupted.
For multiple inverters:
The charging of stacked inverters is synchronized and is governed by the master. The charger settings of
all other inverters are ignored.
No Charging
If the inverter is not charging, several conditions may apply:
The unit is not connected to a qualified AC source. If a generator is present, it may not be running.
The unit is connected to an AC source but the charger has been turned off.
Bulk Stage
This is the first stage in the three-stage charge cycle. It is a constant-current stage which drives the battery
voltage up. This stage typically leaves the batteries at 75% to 90% of their capacity, depending on the
battery type, the exact charger setting, and other conditions.
Voltage Used: Absorb Voltage setting.
Default Set Point (nominal voltage): 14.4 Vdc (12-volt). This is multiplied accordingly for inverters of
other voltages.
The initial DC current may be as high as the charger’s maximum current, depending on conditions.
The current will begin at a high level, but will tend to drop slightly as the voltage rises. This is not a
reduction in charging. It can be viewed as a wattage “tradeoff”. The actual kilowatts used by the charger
are shown in the MATE3 Inverter menu. The reading is usually consistent at this stage. (See page 35.)
Voltage
Inverter now charging to a new set point Inverter has reached the charging set point
No Charge (Source Removed)
Time
Absorption
Set Point
Float
Set Point
Bulk Absorption Float
No Charge