Lynx grounding

Q&A and troubleshooting
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Hello!

We usually bond the negative of the lynx to the main earth terminal.

My first question is how I should think about wire gauge for the grounding cable from the lynx. It seems unreasonable to make it as thick as the DC cables from batteries/inverters. What is the best practice on this? As of now I’ve used the inverter power to give a sense of what’s enough, usually with some precautions, like 15kVA ~16mm2. My reasoning being that it’s thick enough to take a full fault current and last longer than the fuses.

Second question; when is it advised to not ground the lynx (or DC negative overall)?

Is the main point of it to avoid AC currents on the DC side if there’s a major problem with the inverter? Or is it to trip a fuse if there’s a damaged DC cable connected to “ground”?

Thank you!

1 Like
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15 kva through 16 mm² - interesting!

I’m sure that I read that the ground cable must be as big as the smallest supply cable.

The issue will not be the cable but the method of grounding the ground cable into the ground itself.

Multiple earth stakes and even earth plates buried deep (> 2 metres) into moist soil are always required.

The old days of connecting to the copper water supply pipelines are long gone with pex piping routinely replacing copper.