Cerbo GX Installation

down. Examples are Inverter overload, high temperature or low battery voltage. It is therefore recommended to power the GX
device from the battery.
Isolation
Because the Cerbo GX is connected to many different products, please ensure that proper care is taken with isolation to prevent
ground loops. In 99% of installations this will not be a problem.
• The VE.Bus ports are isolated
• The VE.Direct ports are isolated
• The VE.Can ports are not isolated.
• The USB ports are not isolated. Connecting a Wi-Fi Dongle or GPS Dongle will not create a problem as it is not connected to
another power supply. Even though there will be ground loop when you mount a separately-powered USB hub, during
extensive testing we have not found that it caused any issues.
• The Ethernet port is isolated, except for the shield: use unshielded UTP cables for the Ethernet network
Extending USB ports by use of a self-powered USB hub
Although the number of USB ports can be extended by using a hub, there is a limit to the amount of power that the onboard USB
port can provide. When extending the number of USB ports, we recommend you always use powered USB hubs. And to minimize
the chance of issues, be sure to use good-quality USB hubs. As Victron also offers a VE.Direct to USB adapter, you can use this
arrangement to increase the number of VE.Direct devices you can connect to your system, please see this document for the limit
of how many devices can be attached to various different GX devices.
2.3. Connecting Victron products
2.3.1. Multis/Quattros/Inverters (VE.Bus products)
In order to keep this document short we are going to refer to all Multis, Quattros and Inverters as VE.Bus products.
The earliest version of the VE.Bus devices which can be connected to the Cerbo GX is 19xx111 or 20xx111, which were released
in 2007. VE.Bus firmware 26xxxxx and 27xxxxx are also supported …but 18xxxxx is not.
Note that it is not possible to use the Remote On/Off (header on the VE.Bus control PCB) in combination with a Cerbo GX. There
should be wire between the left and middle terminal, as it is when shipped from the factory. In case a wired switch that disables
the system is required, use the Safety Switch Assistant.
Single VE.Bus products
To connect a single VE.Bus product, connect it to one of the VE.Bus sockets on the back of the Cerbo GX. Both sockets are
identical, use either one. Use a standard RJ45 UTP cable, see our pricelist.
Parallel, split- and three-phase VE.Bus systems
To connect multiple VE.Bus products, configured as a parallel, split-phase or three phase VE.Bus system, connect either the first
or the last VE.Bus product in the chain to either one of the VE.Bus sockets on the back of the Cerbo GX. Use a standard RJ45
UTP cable, see our pricelist.
VE.Bus systems with Lithium batteries and a VE.Bus BMS
• Connect the Cerbo GX to the socket labelled ‘MultiPlus/Quattro’, or to one of the Multis/Quattros in the system. Do not connect
it to the Remote panel socket on the VE.Bus BMS.
• Note that it will not be possible to control the On/Off/Charger Only switch. This option is automatically disabled in the Cerbo GX
menu when a VE.Bus BMS is used. The only way to control a Multi or Quattro when used with a VE.Bus BMS is to add a Digital
Multi Control to the system. Setting the input current limit is possible in systems with a VE.Bus BMS.
• Combining MultiPlus/Quattro with a VE.Bus BMS and a Digital Multi Control is possible. Simply connect the Digital Multi Control
to the RJ-45 socket on the VE.Bus BMS labelled Remote panel.
• To allow auto-power-down in the Cerbo GX in case of a low battery, make sure the Cerbo GX is powered via the VE.Bus BMS:
connect Power in V+ on the Cerbo GX to Load disconnect on the VE.Bus BMS. And connect both negative leads to the
negative stub of a common Battery.
Combining the Cerbo GX with a Digital Multi Control
It is possible to connect both a Cerbo GX and a Digital Multi control to a VE.Bus system. The ability to switch the product On, Off
or set it to Charger Only via the Cerbo GX will be disabled. The same applies to the input current limit: when there is a Digital
Multi Control in the system, the input current limit which is set at that control panel will be the master-setting, and changing it on
the Cerbo GX will not be possible.
Connecting multiple VE.Bus systems to a single Cerbo GX
Only one VE.Bus system can be connected to the VE.Bus ports on the back of the Cerbo GX. The professional way to to monitor
more systems is to add a second Cerbo GX
If you do require to connect more than one system to the same Cerbo GX, use an MK3-USB. Functionality will be limited:
Cerbo GX Manual
Page 3 Installation