Victron energy Venus GX Manual page 36

2- For detailed wiring/installation notes and specifications refer to the IMT Si-RS485 series solar
irradiance sensor 'Quick Reference Guide' and Victron RS485 to USB interface cable 'Datasheet'.
To ensure signal integrity and robust operation, particularly ensure that;
Extension cabling complies with the minimum cross-sectional area specifications in the related
table - dependent on DC supply voltage and cable length
Extension cabling has appropriate shielding and twisted pair cores
The original cable attached to the Victron RS485 to USB interface is reduced to a maximum
length of 20cm in installations where the total cable length is over 10m or there are
installation/site specific interference issues – in this case appropriate/high quality cabling should
be used for the entire cable length, rather than only for the extension length
Cabling is installed separated/away from the main DC or AC power cabling
All wiring is properly terminated (including unused wires) and properly isolated from
weather/water ingress
The sensor housing is not opened or tampered with during installation - as sealing integrity will
be compromised (and warranty void)
3- The IMT Si-RS485TC series solar irradiance sensor includes internal Galvanic Isolation (up to 1000V)
between power supply and RS485 Modbus circuits, accordingly the non-isolated Victron RS485 to USB
interface is suitable for most installations.
However, if an isolated RS485 to USB interface is preferred the only compatible device is Hjelmslund
Electronics USB485-STIXL (any others type will not be recognised by the GX device).
1.10.5 Multiple Sensors
It is possible to connect multiple IMT Si-RS485 series solar irradiance sensors to a common Victron GX
device, however a dedicated Victron RS485 to USB interface is required for each individual unit.
Multiple units cannot be combined on a single interface (as this is not supported by the related Venus
OS software).
1.10.6 Configuration
There is normally no need for any special/additional configuration – the default 'as shipped'
configuration is compatible for communication with a Victron GX device.
However, in cases where the IMT Si-RS485 series solar irradiance sensor has been previously used in
another system and/or the settings changed for any reason, it is necessary to restore the default
configuration before further use.
To revise the configuration, download the IMT 'Si-MODBUS-Configuration software tool'. Follow the
instructions in the IMT 'Si Modbus Configurator Documentation'. and check/update the following
settings:
Color Control GX manual