PV DC ground fault protection

brackstone said:

After a bit of reading on this. It seems this may only be an issue on USA systems as they bond the DC PV line to ground. If this is bonded then any ground fault on a PV array will have a current path along the gound wire and back to the PV arry via the bonded DC line.

So if this DC line was not bonded in the first place then there will be no fault path to create a problem.

The safety issue with not bonding the DC line to ground is any fault will not be showing and a pertetial electric shock senario arrises if a person touched the ground and return PV line at same time.

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Don't know if still useful but for anyone interested, grounding of PV systems has been a contentious issue since 1994. See this article article.pdf . According to this article ungrounded Class II PV systems (no system grounding but frames etc. grounded) seems to be the safest option but it remains a trade-off and there is unfortunately no clear cut simple answer. Grounding in general even on AC systems is not an easy topic. This widely known long video by Mike Holt about grounding is testimony to what a complicated subject it is

As a side note, the matter of Ground Fault Protection remains a bit of a predicament for me. I am using Victron SmartSolar MPPT's and as such no system grounding i.e. neither of the PV cables are grounded only the frames. I am not comfortable with the scenario of ground faults causing ground current and would also like to add a GFPD device. However, this is complicated by availability and affordability of GFPD's where I live and on top of this the implementation of GFP leads to a break in ground (based on the solutions by Midnite, Earth Guard, Morninstar which I have seen) which in turn creates the problem of compromised equipment grounding on MPPT casing etc. So between a rock and a hard place. Most other installations like mine, in my area, simply have non-system grounded PV but frames grounded, no GFPD and a decision to look the other way and "hear no evil see no evil" as far as potential ground currents go...

Triton said:

Don't know if still useful but for anyone interested, grounding of PV systems has been a contentious issue since 1994. See this article article.pdf . According to this article ungrounded Class II PV systems (no system grounding but frames etc. grounded) seems to be the safest option but it remains a trade-off and there is unfortunately no clear cut simple answer. Grounding in general even on AC systems is not an easy topic. This widely known long video by Mike Holt about grounding is testimony to what a complicated subject it is

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