MultiPlus-II GX 24 V 3 kVA — front with GX display
Inverter/charger
MultiPlus-II GX
This is a MultiPlus-II with built-in GX device and a 2 × 16 character display. Without a separate Cerbo GX, it gives local system monitoring, VRM access via Ethernet or Wi-Fi, a VE.Direct port and a BMS-Can port for a compatible CAN-bus managed battery.
According to the MultiPlus-II GX datasheets and the MultiPlus-II GX manual (rev 13, 07/2026). Independent description. Sources
What it is for
MultiPlus-II with control panel and VRM in one enclosure
Inside is a standard MultiPlus-II: inverter, charger and transfer switch. The difference is the built-in GX card — backlit 2 × 16 character display, Ethernet socket and Wi-Fi. You can see the system locally and in the VRM portal, without adding a separate Cerbo GX.
The manufacturer intends it for grid-tied and off-grid energy storage and for backup power: when the grid disappears, the unit takes over the loads from the battery in a fraction of a second, and sends surplus from the panels to charging.
display with live values and the VRM portal via Ethernet, Wi-Fi or a GX LTE modem,
VE.Direct port to a solar charge controller or battery monitor and BMS-Can 500 kbit/s to a battery with BMS,
two AC outputs — the second disconnects loads when there is no input supply.
Display instead of a separate screen. The button next to the screen lights it up and scrolls through the readings; after five minutes the backlight turns off automatically.
VRM without an extra device
The same view on the device screen and on your phone
The GX card sends data to the free VRM portal — you need internet, ideally via Ethernet cable to the router. History, alarms and remote settings are visible there too.
Features
What the MultiPlus-II GX can do
2 × 16 character display
Shows PV power and voltage, state of charge, daily yield, battery state of charge and power, IP address, and AC input and output power — in a three-phase system separately for each phase.
Ethernet, Wi-Fi and VRM
Local and remote monitoring via the VRM portal. Internet is required for the connection — the manufacturer recommends an Ethernet cable to the router; without a local network, the GX LTE modem remains.
BMS-Can 500 kbit/s
For compatible batteries with a CAN-based BMS. This is not a VE.Can port — VE.Can MPPT solar charge controllers and VE.Can Lynx Shunt are not supported.
VE.Direct and USB
One VE.Direct port — for a SmartSolar solar charge controller or battery monitor; its data goes to the display and to VRM. The USB socket accepts, among other things, a memory stick with a GX card settings restore file.
PowerControl and PowerAssist
Set the input current limit from shore power or a generator in the GX device, the app or on the Digital Multi Control panel. PowerAssist adds up to 3 kVA (13 A) from the battery — with a 32 A input, this gives up to 45 A at the output.
Two AC outputs
AC-out-1 works continuously. AC-out-2 disconnects the load when the unit switches to battery, and reconnects about 2 minutes after the input voltage returns — long enough for the generator to stabilise.
Relay and two I/O ports
Programmable relay, for example for generator start, and two programmable analogue-digital ports — used, among other things, for the “allow to charge” and “allow to discharge” signals from a lithium battery BMS.
Built-in battery monitor
Controls the relay according to the set depth of discharge, voltage or load — with delay if you set it that way — and switches it off after the bulk phase ends.
Interaction with a PV inverter
Surplus from the grid-tie inverter on the AC output charges the battery. When there is no grid, the unit slightly raises the frequency to limit that inverter’s output (frequency shift).
Adaptive charger
Bulk – absorption – float – storage, with BatterySafe mode and shortened or extended absorption. The temperature sensor and Vsense wires compensate for voltage drop and battery heat.
Parallel and three-phase
Up to six identical units in parallel, in a three-phase star configuration (not delta). Only one GX device may operate in the whole system — that is why the manufacturer recommends models without built-in GX there.
ESS and grid code
To export energy to the grid, you must set the grid code in VEConfigure; changing the settings later requires a password from the distributor. When operating in parallel with the grid, current is measured by an external current transformer.
Models
Comparison
24/3000/70-32 GX. The smallest model, the only 24 V unit: 3,000 VA, charging up to 70 A, 32 A transfer switch, 20 kg.
48/5000/70-50 GX. 5,000 VA and 9,000 W peak, 70 A charging, 50 A transfer switch — the heaviest in the family (31 kg).
48/6k5/100-50 GX. 6 kW continuous power, 11 kW for one minute and charging up to 100 A; IP21 enclosure.
Model
Continuous power at 25 °C
Peak
Max. charging at 25 °C
Transfer switch / AC input
Weight
24/3000/70-32 GX
3000 VA / 2400 W
5500 W
70 A
32 A
20 kg
48/3000/35-32 GX
3000 VA / 2400 W
5500 W
35 A
32 A
20 kg
48/4k5/55-32 GX
4 kW
7 kW / 1 min
55 A
32 A
21.4 kg
48/5000/70-50 GX
5000 VA / 4000 W
9000 W
70 A
50 A
31 kg
48/6k5/100-50 GX
6 kW
11 kW / 1 min
100 A
50 A
29 kg
DC input: 19–33 V (24 V), 38–66 V (48/3000 and 48/5000), 38–60 V (4k5 and 6k5). Output 230 V ± 2%, 50 Hz. Charger input 187–265 V, 45–65 Hz. Auxiliary AC output AC-out-2 up to 32 A. For 48/4k5/55-32 GX at 40 °C the maximum charging current is 50 A, and for 48/6k5/100-50 GX — 95 A. Power decreases with temperature (for example, 48/5000: 3700 W at 40 °C, 3000 W at 65 °C). Ingress protection: IP22 for 24/3000, 48/3000 and 48/5000; IP21 for 48/4k5 and 48/6k5. Operating range: from −40 to +65 °C with fan cooling. Selected MultiPlus-II GX models are included in the Polish PTPiREE list of certificates — see home with energy storage.
48/3000/35-32 GX. A 48 V version with 3000 VA output: charging up to 35 A, 32 A transfer switch and the same enclosure as the 24 V model.
Typical setup
How to connect MultiPlus-II GX
This is a MultiPlus-II with a built-in GX device: without a separate Cerbo GX it gives system monitoring and the VRM portal. In a parallel or three-phase system only one GX device can operate. Illustrative diagram.
direct current (DC)alternating current (AC)communication
Hover over the diagram element or tap it.
BatteryDC fuse close to the battery; disconnect AC and the battery before work.
Mains to AC-inSet the input current limit in the app, DMC panel or GX device.
LoadsAC-out-1 always, AC-out-2 only when mains is present.
VE.DirectSmartSolar charge controller or battery monitor — data is visible on the display and in VRM.
VRMEthernet or Wi-Fi; in a parallel system only one GX device.
Connections
What is under the service cover
Everything in one place. Communication sockets are in the top left corner, next to the AC-OUT-1, AC-OUT-2 and AC-IN terminal strips, with battery terminals on the right.
Top view. The cover is removed after undoing the two screws on the underside of the enclosure — the interior must remain accessible after installation.
Cable glands from below. AC and DC cables enter from underneath, so they do not block the display or sockets.
AC terminal strips — terminal order from the left: N (neutral), PE (protective earth), L (line). Do not swap N and L. Torque on the AC-out-2 terminals: max. 2 Nm.
Battery terminals — M8 bolts, 12 Nm torque, tightened with a torque wrench and insulated socket. Connect the negative cable first, then the positive; a spark may appear when connecting.
Communication sockets — Ethernet, Wi-Fi (antenna), USB, VE.Direct, BMS-Can and two VE.Bus sockets for the remote panel or parallel connection.
Auxiliary contacts — programmable relay, two analogue/digital ports (AUX), remote on/off and terminals for Vsense and the temperature sensor.
Vsense — two 0.75 mm² wires measure the voltage directly at the battery. The charger will compensate for a voltage drop of up to 1 V per pole, and at greater values it will reduce the charging current.
Temperature sensor — mounted on the negative battery terminal. It is not included with 48 V models and must be ordered separately (ASS000001000).
Larger model, same layout. In the 48 V 5 kVA version the terminals and strips are spaced further apart, but the arrangement remains the same.
Which model
MultiPlus-II GX, MultiPlus-II with Cerbo GX or EasySolar-II GX
This sheet
MultiPlus-II GX
Inverter/charger with the GX card inside. Choose it when the system has one VE.Direct device and a battery communicating over BMS-Can, and you want one enclosure and a shorter cable list.
GX inside, 2 × 16 display
Advanced system
MultiPlus-II + Cerbo GX
A separate GX centre provides VE.Can and BMS-Can ports, several VE.Direct inputs and a GX Touch touchscreen. It is also the only option for parallel and three-phase operation. Cerbo GX datasheet.
VE.Can + several VE.Direct
Ready-made PV set
EasySolar-II GX
MultiPlus-II, SmartSolar charge controller and GX device factory-connected in one enclosure — for when the panels are part of the project from the start. EasySolar-II GX datasheet.
VE.Can and BMS-Can (both configurable in Cerbo GX MK2)
VE.Direct
1 port
several ports (in Cerbo GX)
Installation
one device, fewer cables
separate GX module anywhere
MultiPlus-II GX is suitable where one VE.Direct controller and a battery with BMS over BMS-Can are enough. For VE.Can devices (Lynx Smart BMS, VE.Can charge controllers) or several VE.Direct devices, a standard MultiPlus-II with Cerbo GX is a better choice.
Installation
Installation and connection rules
This is work for an installer
The device operates at dangerous voltage and should be installed under the supervision of a suitably qualified person, in accordance with local regulations. Disconnect AC power and the battery before work.
DC fuse and cable cross-section
The manual specifies for these models: 24/3000/70 — battery 200–700 Ah, 300 A fuse, 50 mm² at 0–5 m; 48/3000/35 — 100–400 Ah, 125 A, 35 mm²; 48/5000/70 — 200–800 Ah, 200 A, 70 mm². Copper cables with 90 °C insulation, at 5–10 m 95, 70 and 120 mm² respectively. For 48/4k5 and 48/6k5, check the data in the manual for those models.
Location
Dry, well ventilated and as close to the battery as possible — but never directly above it. Leave at least 10 cm of free space around the enclosure; too high an ambient temperature shortens the service life of the device, reduces charging current and peak power. Wall mounting: hook and two holes at the back, horizontal or vertical — vertical is better for cooling.
Earthing and RCD
This is a Class I product — it must have a continuous earth connection. The internal earth relay connects the output N to the enclosure when there is no external supply, and opens before the input relay closes. The mains transformer inside eliminates DC components, so an RCD type A is sufficient. In a mobile installation the enclosure is connected to the chassis or hull, and on a boat an isolation transformer is used instead of direct shore earthing.
Configuration
Inverter and charger settings are changed via the MK3-USB interface (VictronConnect or VEConfigure), and remotely via the GX card and VRM portal. With a Victron LiFePO4 battery with Lynx Smart BMS, set the remote mode to “Remote on/off”, and with smallBMS — “2-wire BMS”.
Wall mounting. There is a hook and two holes on the back of the enclosure — the mounting surface must support the weight of the device (20–31 kg depending on the model).
Sequence: remove the service cover (two screws on the underside), check battery polarity with a multimeter, connect the negative first, then the positive, and finally the AC and communication cables. Reverse polarity will damage the device and is not covered by the warranty.
AC input protect with a breaker no larger than the switch on that model (32 A or 50 A); if the shore power connection or generator is rated lower, size the protection to the source. On the AC-out-1 output, you need an RCD and overcurrent protection matched to the load.
Parallel operation: up to six identical units, the same firmware version, identical DC cable cross-sections and lengths, the battery negative cable always connected directly (without a fuse), UTP cables run directly from device to device — no splitters. In the whole system, only one GX device and one remote panel.
Three-phase only in star (Y) configuration, never delta. With AS4777.2 grid code, two units per phase are allowed. It is worth agreeing such a setup with the distributor.
Remote control: with a normal switch or a Digital Multi Control panel in the VE.Bus socket — it works only when the switch on the device is in the “on” position. The panel has an input current limit knob.
AC terminals and battery terminals. From the left, N, PE and L on each terminal strip; battery terminals with covers on the right, and below them cable glands through which the cables enter.
Errors
Messages and codes on the display
The GX card display shows inverter and charger messages, VE.Bus codes, and codes from the connected MPPT solar charge controller. The message stays on the screen until the cause disappears. We have collected the full list of VE.Bus codes in the VE.Bus error codes section.
Low battery
Low battery voltage
The voltage has dropped below the threshold — if it falls further, the inverter switches off. Charge the battery or check the DC connections.
Clears automaticallyafter the battery has been charged.
Overload
Overloaded
The load exceeds the rated power; if the overload is large, the inverter stops working. Reduce the load.
Clears automaticallyafter the load is reduced.
Over Temperature
High temperature
The surroundings are too warm or the load is too high. Provide a cool, ventilated location and 10 cm clearance around the enclosure.
Clears itselfafter cooling down.
Low Bat V Overload
Low voltage and overload
The battery is weak and the load is too high at the same time. Charge the battery, disconnect some loads, and consider a larger battery bank and shorter or thicker DC cables.
High DC Ripple
Excessive DC ripple
Ripple at the terminals exceeds 1.5 V RMS — usually because the battery cables are too thin or too long, connections are loose, or the battery bank capacity is too small.
DC Ripple Shutdown
Ripple shutdown
The inverter has shut down due to ripple. Improve the DC wiring, increase battery capacity, and restart the unit with the switch.
Does not clear automaticallyrequires a restart.
Bulk protection
Bulk phase protection
Charging in bulk phase lasted for more than 10 hours, which may indicate a damaged cell. Check the battery; the error clears when the unit is switched off and on.
Does not clear automaticallyrequires a restart.
No voltage on AC-out-2
AC-out-2 no voltage
The unit is running from the battery — this output works only when AC is present on the input and returns with about a 2-minute delay. Also check the AC input fuse.
Clears automaticallywhen mains power returns.
Charger not working
No charging from mains
Input voltage outside the 185–265 V range or frequency outside the set range (factory default 45–65 Hz), the AC input protection has tripped, or the battery fuse has blown. If the generator output voltage is distorted, enable WeakAC and the dynamic current limiter.
Error 1
Switched off by another phase
One of the other phases in the system has switched off. Check what happened on that phase.
Error 3
Wrong number of devices
The system has found fewer or more units than the configuration expects. Reconfigure the system, check the communication cables, switch everything off and on.
Error 4
No connection with other devices
No other device was detected in the system — check the UTP cables between the units.
Error 5, 18
Overvoltage on AC output
Excessively high voltage appeared at the output. Check the AC wiring.
Error 10
Time synchronisation problem
This should not occur with a correct installation — check the communication cables.
Error 14
Device is not sending data
Usually a short circuit in the communication cable — check the UTP cables.
Error 17
Master unit change
Another device has taken over as “master” because the original one stopped responding. Check that unit and the cables.
Error 24
Switch-over protection
This should not occur with a correct installation. Switch all devices off and on; if it returns, check the installation and consider raising the lower input voltage threshold to 210 V (factory default 180 V).
Error 25
Incompatible firmware versions
One of the devices has firmware that is too old. Switch the units on one by one until the error returns — update the last one you switched on.
Error 26
Internal error
This should not occur. Switch all devices off and on; if it repeats, contact the distributor.
Questions
Frequently asked questions about MultiPlus-II GX
How is it different from a standard MultiPlus-II?
Only by the built-in GX card with a 2 × 16 character display: you get system monitoring, the VRM portal via Ethernet or Wi-Fi, a VE.Direct port, USB, and a BMS-Can port. The inverter, charger, PowerControl and PowerAssist, two AC outputs and the ground relay work as in MultiPlus-II.
Can I use several units in a parallel system?
Up to six identical units can work in parallel, but there can be only one GX device in the system. To combine several GX models, you have to disconnect the internal connection of the GX card — that is why the manufacturer recommends models without built-in GX and a separate Cerbo GX in such setups.
Can I connect a VE.Can MPPT solar charge controller to BMS-Can?
No. BMS-Can (500 kbit/s) supports compatible batteries with a BMS communicating over CAN. According to the manual, VE.Can MPPT solar charge controllers and Lynx Shunt VE.Can are not supported. Connect the solar charge controller with a VE.Direct cable.
When does AC-out-2 work?
Only when AC is present on the input. When mains power fails, this output disconnects immediately, and when it returns, it comes back after about 2 minutes — so the generator has time to stabilise. AC-out-1 always works.
How do I connect the solar charge controller?
With a VE.Direct cable to the port in the connection compartment — the controller data then appears on the display and in the VRM portal. How to size the controller for the panels is described in the guide, and the MPPT calculator will calculate the string size.
Does the GX card work when the inverter is switched off?
It depends how you switch it off. The switch on the enclosure or the remote on/off terminals also turn off the GX card. Switching off from the Digital Multi Control panel, from the GX menu, or automatic shutdown after an alarm (low voltage, overheating) leaves the GX card on — data still goes to VRM.
What does the display show and how do you switch it?
The button next to the screen first increases the backlight (it turns off automatically after 5 minutes), and further presses scroll through the screens: panel power and voltage, daily yield, charge state, state of charge and battery power, IP address with connection type, and AC input and output power. In a three-phase system, readings for each phase are added.
Is a battery temperature sensor included?
Not in 48 V models — order it separately under part number ASS000001000. Fit the sensor to the negative battery terminal; it reduces the charge voltage as the battery warms up.
How do I restore the GX device to factory settings?
With the file venus-data-90-reset-all.tgz written to an empty USB flash drive formatted in FAT32 (do not unpack it or change its name). Turn the device off, insert the drive, turn it on, wait for the GX device to start, then remove the drive. The procedure requires Venus 2.12 firmware or later and deletes, among other things, a forgotten Remote Console password.
Can I feed energy back into the grid?
Yes, in an ESS system — but you must set the grid code in VEConfigure and meet the local grid-connection requirements. Any later change to parameters related to the grid code requires a password from the distributor. Selected MultiPlus-II GX models are listed in the Polish PTPiREE certificate register — see the house with energy storage wiring diagram for details.
