The Venus GX supports a maximum of 6 VE.Direct devices, regardless of whether they are connected via VE.Direct ports or USB. However, this limit may be lower in complex systems, for example, those with multiple PV inverters or synchronised inverters. Always include some headroom in your system design to ensure reliable operation.
The following mounting options and accessories are available for purchase:
The device is powered via the Power in V+ connector and accepts 8 to 70V DC. It cannot be powered through any other connection (e.g. Ethernet or USB). The supplied DC power cable includes an inline 3.15 A slow-blow fuse.
Powering with a VE.Bus BMS
When using the VGX in an installation with a VE.Bus BMS, connect the Power in V+ terminal on the VGX to the 'Load disconnect' terminal on the VE.Bus BMS. Connect both negative leads to the negative busbar or common battery negative. This is not necessary for the VE.Bus BMS V2 and VE.Bus BMS NG, as both feature a GX-Power output.
Important: Powering from the AC-out terminal of a VE.Bus Inverter, Multi or Quattro
Powering the GX device with an AC adapter connected to the AC-out of a VE.Bus device (e.g. Inverter, Multi, or Quattro) can cause a deadlock:
After a fault or black start, the VE.Bus devices will not boot because the VGX is unpowered.
The VGX cannot boot because the inverter/charger is off, causing a cycle.
Temporary workaround:
Briefly unplug the VE.Bus cable from the GX device to allow the VE.Bus products to restart.
Permanent solution:
Modify the RJ45 cabling. See FAQ Q20 for more information about this.
Recommendation:
Avoid powering the GX device from the AC-out of an inverter/charger. In the event of a shutdown due to inverter overload, high temperature, or low battery voltage, the GX device will also shut down, losing all monitoring and remote access. It is strongly recommended to power the GX device directly from the battery.
Isolation considerations
The GX device connects to various system components. To prevent ground loops, ensure appropriate isolation practices are followed. In most cases, this is not an issue, but proper system design remains essential.
Port type | Cerbo GX | Cerbo GX MK2 | Ekrano GX | Venus GX |
|---|---|---|---|---|
VE.Bus | Isolated | Isolated | Isolated | Isolated |
VE.Direct | Isolated | Isolated | Isolated | Isolated |
VE.Can | Not isolated | 1) | 1) | Isolated |
USB 3) | Not isolated | Not isolated | Not isolated | Not isolated |
Ethernet 2) | Isolated | Isolated | Isolated | Isolated |
1) VE.Can port 1 is galvanically isolated, VE.Can port 2 is non-isolated 2) The Ethernet port is isolated, except for the shield: use unshielded UTP cables for the Ethernet network. 3) USB ports are not isolated. Connecting a WiFi dongle or GPS dongle does not create any problems, as these devices are not powered by an external supply. Even when using a separately powered USB hub, a ground loop may occur. However, extensive testing has shown that this does not cause operational issues. | ||||
Extending USB Ports
The number of USB ports can be expanded using a USB hub. However, the onboard USB ports have limited power availability.
Recommendation
Always use powered USB hubs and select high-quality products to minimise issues.
To increase the number of VE.Direct devices, you can use a VE.Direct to USB adapter. Please see this document for the limit of how many devices can be attached to various different GX devices.
The Venus GX has potential-free Normally Open (NO) and Normally Closed (NC) relay functionality. The relay function can be configured via the GX device menu: Settings → Relay → Function.
Relay 1 is particularly important, as it can be used not only for manual or temperature-based triggering (as with Relay 2), but also as an alarm, generator start/stop or tank pump relay.
 |  |
If the relay function is configured as an Alarm relay, it is possible to reverse the relay polarity via an additional menu.By default, the relay is set to Normally Open (NO). Note: Reversing the polarity to Normally Closed (NC) will result in a slightly higher current consumption of the GX device.
 |  |
Important
Be sure to observe voltage and current limits of the relays as specified in the Technical specifications.