News overview
VE.Bus firmware v501 - fix issue with backup generators in an ESS system

Good day,

Today we released a new firmware version for our inverter/chargers such as the MultiPlus-II and Quattro series, VE.Bus firmware v501.

It fixes a long standing issue where our Quattros, when configured with a grid-code for ESS, would - sometimes - not accept an AC generator on its input.

This is fixed by adding a new option into the Grid-tab, allowing to set that AC Input 1 is a Generator. 

This fix applies to ESS systems using a Quattro-II, and having a Generator for backup. But also applies to systems using the larger Quattros, typically used in combination with an external anti-islanding relay. A combination certified and approved for the German VDE-4105.

Note that besides setting the AC Input 1 to be a generator, which fixes above described issue, it also allows the common Transferswitch settings to be set. Typically used to set a higher AC low disconnect, to prevent overload issues when stopping the generator.


Should the generator be wired to AC Input 1 or AC Input 2?

The general recommendation is to wire the generator to AC input 1. The main reason is that when the battery is completely empty or disconnected, a Quattro can only start from AC input 1 and not AC input 2.


Further improvements coming, Venus OS v3.00 (UPDATED 2023-05-30)

There used to be a disadvantage on wiring the generator to AC input 1, which relates to the Generator start/stop feature in the GX devices ie. a Cerbo. But that is solved, since per Venus OS v3.00, released on 2023-05-30, it can also automatically stop a generator when wired to AC input one. Until Venus OS v3.00, this was only possible for systems having the generator wired to AC input 2.

Venus OS v3.00 includes several generator related improvements, the full list is:

  • Add option to stop back-up generator once grid has returned, also when generator is wired to AC in 1
  • Add warm-up feature: start generator; and run for a configurable time while not yet connecting to it.
  • Add cool-down feature. Same, but then the other way around.
  • More accurate reporting of generator run hours to VRM.


How to install VE.Bus firmware 502:

First of all, note that it is not recommended to keep this firmware type, used in the inverter/charger, up to date. Stable inverter/charger systems should be left with their current firmware. Here is when to perform a firmware update:

  • During commissioning / first install;
  • When trouble shooting;
  • To add a new feature that is required by the installation.

Warning: updating the firmware of this product range is strongly adviced to be carried out by trained personel only. Doing the update will cause all settings to be reset to their default: requiring the product to be reconfigured.

For further information:

A new version of VictronConnect, that includes firmware 501, was released on 2023-01-18.


2023-02-02 - Updated to add note on AC in 1 vs AC in 2.