3. Installation
3.1. Venus GX Overview of connections
3.2. Mounting options and accessories
The following mounting options and accessories are available for purchase:
3.3. Powering the Venus GX
The device is powered by using the Power in V+ connector. It accepts 8 to 70V DC. The device will not power itself from any of the other connections (eg network). The supplied DC power cable includes an inline 3.15A slow blow fuse.
When the VGX is used in an installation with a VE.Bus BMS, connect the Power in V+ on the VGX to the terminal labelled 'Load disconnect' on the VE.Bus BMS. Connect both negative leads to the negative stub of a common battery.
A cautionary word about powering from the AC-out terminal of a VE.Bus Inverter, Multi or Quattro:
If you power the VGX from an AC adaptor connected to the AC-out port of any VE.Bus product (Inverter, Multi or Quattro), then a deadlock will occur after the VE.Bus products are powered-down for any reason (after any operational fault or during a black start). The VE.Bus devices will not boot-up until the VGX has power …but the VGX will not boot-up until it has power. This deadlock can be rectified by briefly unplugging the VGX VE.Bus cable at which point you will observe the VE.Bus products will immediately begin to boot-up.
Or a modification can be done to the RJ45 cabling. See FAQ Q20 for more information about this.
Note that both with or without above modification, powering the monitoring equipment with the AC-out of an inverter/charger (of course) has the disadvantage that all monitoring is shut down when there is a problem that causes the inverter/charger to shut 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 VGX 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.
VE.Bus ports are isolated
VE.Direct ports are isolated
VE.Can ports are isolated
BMS-Can ports are not isolated
USB ports are not isolated. Connecting a WiFi 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.
3.4. Relay connections
The Venus GX has potential-free Normally Open (NO) and Normally Closed (NC) relay functionality. The function of the relays can be set via the GX menu, Settings → Relay → Function.
Relay 1 is of particular importance because, in addition to manual and temperature-related triggering (also applies to relay 2), it can also be used as an alarm, generator start/stop or tank pump relay.
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If the relay function is configured as an Alarm relay, it is possible to reverse the polarity of the relay via an additional menu. The default setting is Normally open. Please note that reversing the polarity to Normally closed will result in a slightly higher current consumption of the GX device.
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