Victron energy MultiPlus-II User manual

MultiPlus-II inverter/charger
off-grid Australia
48/3000/35-32 230V GX and 48/3000/70-50 230V GX
rev 00 - 10/2023
ENGLISH

Table of Contents
1. Safety Instructions ................................................................................................................... 1
2. Description ............................................................................................................................ 3
2.1. Features ...................................................................................................................... 3
2.2. Battery charger .............................................................................................................. 4
2.2.1. Lead-acid batteries ................................................................................................ 4
2.2.2. More on batteries and battery charging ......................................................................... 4
2.2.3. Victron Lithium Battery 12.8V & 25.6V Smart .................................................................. 4
2.2.4. Other lithium batteries ............................................................................................ 5
3. Operation .............................................................................................................................. 6
3.1. On/off/charger-only switch .................................................................................................. 6
3.2. Remote control .............................................................................................................. 6
3.3. GX card and LCD interface ................................................................................................. 6
3.3.1. On/Off behaviour .................................................................................................. 6
3.3.2. Push button behaviour ............................................................................................ 6
3.3.3. Information displayed ............................................................................................. 6
3.3.4. Error Code Display ................................................................................................ 7
3.4. Shut down procedure ....................................................................................................... 7
4. Installation ............................................................................................................................. 8
4.1. Mounting ...................................................................................................................... 8
4.2. DC connection ............................................................................................................... 8
4.3. AC connection ............................................................................................................... 9
4.4. Connection to the VRM Portal ........................................................................................... 10
4.5. Optional connections ...................................................................................................... 10
4.5.1. Remote control .................................................................................................. 10
4.5.2. Programmable relay ............................................................................................ 10
4.5.3. Programmable analogue/digital input/output ports .......................................................... 10
4.5.4. Voltage sense .................................................................................................... 10
4.5.5. Temperature sensor ............................................................................................. 10
5. Configuration ....................................................................................................................... 11
5.1. Standard settings: ready for use ......................................................................................... 11
5.2. Configuring ................................................................................................................. 11
5.2.1. VictronConnect .................................................................................................. 12
5.2.2. VEConfigure ..................................................................................................... 12
5.2.3. VE.Bus Quick Configure Setup ................................................................................ 12
5.2.4. VE.Bus System Configurator .................................................................................. 12
5.3. Firmware ................................................................................................................... 12
6. Maintenance ......................................................................................................................... 13
7. Error Indications ................................................................................................................... 14
7.1. General error indications ................................................................................................. 14
7.2. VE.Bus error codes ....................................................................................................... 15
8. Technical specifications .......................................................................................................... 17
9. Appendix ............................................................................................................................. 19
9.1. Connection Overview ..................................................................................................... 19
9.2. Block diagram .............................................................................................................. 21
9.3. Charge algorithm .......................................................................................................... 21
9.4. Temperature compensation .............................................................................................. 22
9.5. Dimensions ................................................................................................................. 23
MultiPlus-II inverter/charger off-grid Australia

1. Safety Instructions
In general
Please read the documentation supplied with this product first, so that you are familiar with the safety signs and directions before
using the product.
This product is designed and tested in accordance with international standards. The equipment should be used for the designated
application only.
Warning – These servicing instructions are for use by qualified personnel only. To reduce the risk of
electric shock, do not perform any servicing other than that specified in the operating instructions
unless you are qualified to do so
The product is used in combination with a permanent energy source (battery). Even if the equipment is
switched off, a dangerous electrical voltage can occur at the input and/or output terminals. Always switch the
AC power off and disconnect the battery before performing maintenance.
The product contains no internal user-serviceable parts. Do not remove the front panel and do not put the product into operation
unless all panels are fitted. All maintenance should be performed by qualified personnel. Internal fuses are not user replaceable.
A unit with suspected blown fuses should be taken to an authorized service center for evaluation.
Never use the product at sites where gas or dust explosions could occur. Refer to the specifications provided by the manufacturer
of the battery to ensure that the battery is suitable for use with this product. The battery manufacturer's safety instructions should
always be observed.
This appliance is not intended for use by persons (including children) with reduced physical, sensory or mental capabilities, or
lack of experience and knowledge unless they have been given supervision or instruction concerning the use of the appliance by
a person responsible for their safety. Children should be supervised to ensure that they do not play with the appliance.
do not lift heavy objects unassisted.
Installation
Read the installation instructions before commencing installation activities. For electrical work, follow the local national wiring
standard, regulations, and installation instructions.
This product is a safety class I device (supplied with a ground terminal for safety purposes). Its AC input and/or output
terminals must be provided with uninterruptible grounding for safety purposes. An additional grounding point is located
on the outside of the product. The ground conductor should be at least 4mm². If it can be assumed that the grounding
protection is damaged, the product should be taken out of operation and prevented from accidentally being put into operation
again; contact qualified maintenance personnel.
Ensure that the connection cables are provided with fuses and circuit breakers. Never replace a protective device by a
component of a different type. Refer to the manual for the correct part.
Do not invert neutral and phase when connecting the AC.
Check before switching the device on whether the available voltage source conforms to the configuration settings of the product
as described in the manual.
Ensure that the equipment is used under the correct operating conditions. Never operate it in a wet or dusty environment. Ensure
that there is always sufficient free space around the product for ventilation, and those ventilation openings are not blocked. Install
the product in a heatproof environment. Ensure, therefore, that there are no chemicals, plastic parts, curtains or other textiles, etc.
in the immediate vicinity of the equipment.
This inverter is provided with an internal isolation transformer providing reinforced insulation
Transport and storage
On storage or transport of the product, ensure that the AC supply and battery leads are disconnected.
No liability can be accepted for damage in transit if the equipment is not transported in its original packaging.
Store the product in a dry environment; the storage temperature should range from –20°C to 60°C.
Refer to the battery manufacturer's manual for information on transport, storage, charging, recharging, and disposal of the battery.
MultiPlus-II inverter/charger off-grid Australia
Page 1 Safety Instructions

Symbols on the enclosure
Symbol Description
Caution, hot surface
Caution, risk of electric shock
Refer to the operating instructions
IP21 Protected from touch by fingers and objects greater than 12 millimetres. Protected from
condensation.
European conformity
Regulatory compliance mark for Australia & New Zealand
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2. Description
The MultiPlus-II GX is an extremely powerful sine inverter, battery charger and transfer switch together with a GX card with a
2x16-character display in a compact casing.
This unit is for use in off-grid applications such as, marine, automotive, as well as stationary land-based applications.
This manual applies to:
• MultiPlus-II 48/3000/35-32 230V GX
• MultiPlus-II 48/5000/70-50 230V GX
2.1. Features
GX LCD display
A backlit 2 x 16 character display screen shows system parameters.
Automatic and uninterruptible switching
If the AC generator is switched off or fails, the MultiPlus-II will switch over to inverter operation and take over the supply of
the connected devices. This is done so quickly that the operation of computers and other electronic devices is not disturbed
(Uninterruptible Power Supply or UPS functionality). This makes the MultiPlus-II highly suitable as an emergency power system in
off-grid, industrial and telecommunication applications.
Two AC outputs
Besides the usual uninterruptible output (AC-out-1), an auxiliary output (AC-out-2) is available that disconnects its load in the
event of battery operation. Example: an electric boiler that is allowed to operate only if the generator is running. There are several
applications for AC-out-2.
Please enter “AC-out-2” in the search box on our website and find the latest information about other applications.
Three phase capability
Three units can be configured for three-phase output. Up to 6 sets of three units can be parallel connected.
PowerControl – maximum use of limited AC power
The MultiPlus-II can supply a huge charging current. This implies heavy loading of the generator. Therefore a maximum current
can be set. The MultiPlus-II then takes other power users into account and only uses “surplus' current for charging purposes.
PowerAssist – Extended use of generator or shore current: the MultiPlus-II “co-supply” feature
This feature takes the principle of PowerControl to a further dimension, allowing the MultiPlus-II to supplement the capacity of the
alternative AC source. Where peak power is often required only for a limited period, the MultiPlus-II will make sure that insufficient
generator power is immediately compensated for by power from the battery. When the load reduces, the spare power is used to
recharge the battery.
VE.Can port
This port allows a connection of compatible 500 kbps CAN-bus BMS batteries or VE.Can products.
Ethernet and Wifi
Ethernet and WiFi connections allow for local and remote system monitoring, as well as connection to Victron's free VRM portal
for long-term system performance information.
Programmable relay
The MultiPlus-II is equipped with a programmable relay. The relay can be programmed for different applications, for example, as a
starter relay for a generator.
External current transformer (optional)
External current transformer option to implement PowerControl and PowerAssist with external current sensing.
Frequency shift
When AC solar inverters are connected to the output of a MultiPlus-II, excess solar energy is used to recharge the batteries.
Once the absorption voltage is reached, the MultiPlus-II will slightly increase the AC frequency to reduce the output of the solar
inverter.
Built-in Battery Monitor
The ideal solution when the MultiPlus-II is part of a hybrid system (diesel generator, inverter/chargers, storage battery, and
alternative energy). The built-in battery monitor can be set to start and stop the generator:
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• Start at a preset % discharge level, and/or
• start (with a preset delay) at a preset battery voltage, and/or
• start (with a preset delay) at a preset load level.
• Stop at a preset battery voltage, or
• stop (with a preset delay) after the bulk charge phase has been completed, and/or
• stop (with a preset delay) at a preset load level.
Programmable analogue/digital input/output ports (Aux in 1 and Aux in 2, see appendix)
The MultiPlus-II is equipped with 2 analogue/digital input/output ports. These ports can be used for several purposes. One
application is communication with the BMS of a lithium-ion battery.
Programmable settings
All settings can be changed with a computer and free of-charge software, downloadable from our website
www.victronenergy.com.
2.2. Battery charger
2.2.1. Lead-acid batteries
Adaptive 4-stage charge algorithm: bulk – absorption – float – storage
The microprocessor-driven adaptive battery management system can be adjusted for various types of batteries. The adaptive
function automatically adapts the charging process to battery use.
The right amount of charge: variable absorption time
In the event of slight battery discharge, absorption is kept short to prevent overcharging and excessive gas formation. After deep
discharging, the absorption time is automatically extended in order to fully charge the battery.
Preventing damage due to excessive gassing: the BatterySafe mode
If, in order to quickly charge a battery, a high charge current in combination with a high absorption voltage has been chosen,
damage due to excessive gassing will be prevented by automatically limiting the rate of voltage increase once the gassing voltage
has been reached.
Less maintenance and aging when the battery is not in use: the Storage mode
The Storage mode kicks in whenever the battery has not been subjected to discharge during 24 hours. In the Storage mode float
voltage is reduced to 2.2V/cell (13.2V for 12V battery) to minimise gassing and corrosion of the positive plates. Once a week the
voltage is raised back to the absorption level to ‘equalize’ the battery. This feature prevents stratification of the electrolyte and
sulphation, a major cause of early battery failure.
Battery voltage sense: the correct charge voltage
Voltage loss due to cable resistance can be compensated by using the voltage sense facility to measure voltage directly on the
DC bus or on the battery terminals.
Battery voltage and temperature compensation
The temperature sensor (supplied with the product) serves to reduce charging voltage when battery temperature rises. This is
particularly important for maintenance-free batteries, which could otherwise dry out by overcharging.
Two DC outputs for charging two batteries
The main DC terminal can supply the full output current. The second output, intended for charging a starter battery, is limited to
4A and has a slightly lower output voltage (12V and 24V models only).
2.2.2. More on batteries and battery charging
Our book "Energy Unlimited" offers further information on batteries and battery charging and is available free of charge on our
website. It can be downloaded from: https://www.victronenergy.com/upload/documents/Book-Energy-Unlimited-EN.pdf, or a hard
copy can be ordered from: https://www.victronenergy.com/orderbook
For more information on adaptive charging, please refer to the technical paper: Adaptive charging, how it works.
2.2.3. Victron Lithium Battery 12.8V & 25.6V Smart
If Victron Lithium Smart batteries are used, use the VE.Bus BMS V2 or the Lynx Smart BMS.
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2.2.4. Other lithium batteries
If other lithium batteries are used, follow this link for a list of compatible battery types and how to install and configure them:
https://www.victronenergy.com/live/battery_compatibility:start.
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3. Operation
3.1. On/off/charger-only switch
When switched to ‘on’, the MultiPlus-II is fully functional. The inverter will come into operation, and the LED ‘inverter on’ will light
up.
An AC voltage connected to the AC input terminal will be switched through to the AC output terminal, if within specifications. The
inverter will switch off, the ‘mains on’ LED will light up, and the charger commences charging. The ‘bulk’, ‘absorption’ or ‘float’
LEDs will light up, depending on the charger mode.
If the voltage at the ‘AC-in’ terminal is rejected, the inverter will switch on.
When the switch is switched to ‘charger only’, only the battery charger of the MultiPlus-II will operate (if an AC voltage is present).
In this mode, the AC input voltage is also switched through to the ‘AC out’ terminal.
NOTE: When only the charger function is required, ensure that the switch is switched to ‘charger only’. This prevents the inverter
from being switched on if the AC input voltage is lost, thus preventing your batteries from running flat.
3.2. Remote control
The product can be remotely controlled in two ways.
• With an external switch. For the switch to operate the switch on the Multiplus-II needs to be set to “on”.
• With a Digital Multi Control panel. For the panel to operate the switch on the Multiplus-II needs to be set to “on”.
3.3. GX card and LCD interface
The display screen will present useful information about your system.
3.3.1. On/Off behaviour
When the product is switched off with the physical switch on the device or with the Remote On/Off terminals, then the GX card
is off as well. If you switch the product remotely, using a Digital Multi Control, then the GX card will remain powered. Also when
switching the inverter/charger off from within the GX menus, the GX card will remain powered.
Lastly, when the inverter/charger switches itself off due to an alarm, such as low battery or overtemperature, then the GX card will
remain powered and functional as well.
3.3.2. Push button behaviour
When the GX Card is on, pushing the button beside the screen will increase the brightness of the backlight. The backlight will dim
itself again after 5 minutes.
Once the backlight has been activated, pushing the button again will cycle through the available display options. Some options
will be displayed automatically, and others require a button push to display.
3.3.3. Information displayed
• Solar Power, Voltage and Charge state (if connected)
• Solar Daily Yield
• Inverter/charger charge state
• Battery State of Charge, Power and Voltage
• Network IP Address and Connection Type (if connected).
• AC input and output Power
In a system with more than one phase, there will be additional AC input and output information available, eg
• Phase 1 AC input Voltage and Power.
• Phase 1 AC output Voltage and Power
• Phase 2 AC input Voltage and Power.
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• Phase 2 AC output Voltage and Power.
• Phase 3 AC input Voltage and Power.
• Phase 3 AC output Voltage and Power.
3.3.4. Error Code Display
If there is an error with the system, the error code will be displayed on the screen. The screen will display VE.Bus error code
numbers, and MPPT error codes (if connected).
Basic information about the VE.Bus Error codes are in the Error Indications section.
For further details about the error codes please see:
VE.Bus Error Codes
MPPT Error Codes
The error will display until it is cleared.
3.4. Shut down procedure
To switch the MultiPlus-II off, use the on/off/charger-only switch located on the bottom left-hand underside of the case. The middle
position of the switch is the OFF position.
To completely de-power the MultiPlus-II, disconnect the DC fuse or turn off the isolation switch, DC contactor or DC circuit
breaker, located between the battery and the DC terminals of the unit. Note that dangerous residual voltages may still exist inside
the product and at its terminals after shutdown. Never open the product casing or touch bare terminals.
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4. Installation
This product may only be installed by a qualified electrical engineer.
4.1. Mounting
4.2. DC connection
In order to utilise the full capacity of the product, batteries with sufficient capacity and battery cables with sufficient cross-section
should be used. The DC cables must be copper and rated 90ºC. See table.
48/3000/35 48/500/70
Recommended battery capacity (Ah) 100-400 200-800
Recommended DC fuse 125 A 200 A
Recommended cross section (AWG) per + and - connection terminal *, **
0 – 5 m 35 mm² 70 mm²
5 – 10 m 70 mm² 120 mm²
* Follow local installation rules.
** Do not locate battery cables in a closed conduit.
Remark: Internal resistance is an important factor when working with low-capacity batteries. Please consult your supplier or the
relevant sections of our book ‘Energy Unlimited’, downloadable from our website.
Connection Procedure
Proceed as follows to connect the battery cables:
Use a torque wrench with an insulated box spanner in order to avoid shorting the battery.
Recommended torque: 12 Nm (M8 nut)
Avoid shorting the battery cables.
• Undo the two screws at the bottom of the enclosure and remove the service panel
• Connect the battery cables, see Appendix A for a connection overview.
MultiPlus-II inverter/charger off-grid Australia
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