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I have all the bits and am about to install a small off grid system.

I will have qty 2 400W panels in series feeding a Victron 100/30 charge controller going into a 24V 100Ah LiFePo4 battery. I will then use a Buck converter to provide a 12V/10A output for 2 security camera systems and switch/router that provides WiFi in my garage. These 3 devices will consume around 60W or 5A @12V. The switch/router, the main router in the house and the camera systems are all connected over Ethernet.

I should add that I have no intention of adding an Inverter to this system. But I do intend to have a (on grid ie mains) battery charger for those few days in winter when the battery might get low. This will be automated and triggered by the Battery State (%) as reported by the Victron Shunt.

My query is what do i need to do about earthing?

Thanks
 
You shouldn't need any earthing for this as it's an isolated extra low voltage system.
I assume from the mention of a garage that this is going to be in a relation to a building?
 
You shouldn't need any earthing for this as it's an isolated extra low voltage system.
I assume from the mention of a garage that this is going to be in a relation to a building?
The only connection is through the Ethernet cabling.

In the detached garage where the system will be located, I have a 4 camera system and a switch/router for Ethernet and WiFi, both powered by 12V transformers. In the house I have second 4 camera system again currently powered by a 12V transformer. They are all connected by Ethernet which goes on into the rest of the house's Ethernet devices.

I've watched quite a few videos on off grid solar, but am left none the wiser re earthing!
 
The Victron 100/30 charge controller manual section 4.4 gives some guidance on grounding.
You could ground the -ve battery terminal, as suggested by Victron, to an earth rod or equivalent at your garage, if only for EMC purposes for the benefit of the network devices.

The devices presently powered by 12V adapters doubtless have LV fault protection provided by those adapters, and if you are replacing them with a direct connection to a 10A 12V buck converter, I guess you plan to put fuses in the supply to each device.
 
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The Victron 100/30 charge controller manual section 4.4 gives some guidance on grounding.
You could ground the -ve battery terminal, as suggested by Victron, to an earth rod or equivalent at your garage, if only for EMC purposes for the benefit of the network devices.

The devices presently powered by 12V adapters doubtless have LV fault protection provided by those adapters, and if you are replacing them with a direct connection to a 10A 12V buck converter, I guess you plan to put fuses in the supply to each device.
I'll check out the manual, thanks.
 
The ethernet connection is transformer isolated at each end - UNLESS the switches support PoE (power over ethernet) in which case the galvanic isolation is bypassed by the PoE insertion/extraction.
 

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If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
United Kingdom
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DIY or Homeowner (Perhaps seeking pro advice, or an electrician)

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Small off grid static 24V solar system earthing
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