I am a little unclear what you mean exaclty based on some of the verbiage you are using being a little different but I’ll try to answer.
A Victron Multiplus 12/2000, if that is what you are talking about, will have (3) points that need to be grounded.
The DC side should be grounded to the battery(or battery bus before the shunt of course), which should be grounded to chassis. It doesn’t need to be independently grounded to chassis if the rest of the DC system is properly grounded.
The AC side should be grounded properly to the AC side of the circuit.
The inverter chassis ground stud should be grounded to the boat chassis.
Let me know if that makes sense or if I misunderstood your question.
Hi Thank you for your reply ive drawn a little drawing of a simplified set up that i have. Its the earth for the ac side that i need to make sure ive got correct. Do i need to take an earth out of the inverter consumer unit to a point in the boat?
The inverter chassis needs to be grounded to the boat hull, or whatever grounding system you have. Then automatically, the ACouts PE terminal will be grounded. If you leave the neutral-earth bond inside the inverter in place, then also the neutral will be grounded. This is the preferred config. Also see the manual about this
From there you install a three core cable, L N PE, to your consumer unit. The consumer unit does not need an additional ground simply from a technical view. But there could be regulations that make it necessary. I guess since you are talking about consumer unit you are based in the UK, so @pwfarnell could maybe help further if im not mistaken.
As for your diagram, to me your ground connection from the inverter chassis to the negative busbar is not correct. The negative busbar is an active component in your system, it should not serve double duty as a safety component as well. Use a separate conductor from the inverter chassis directly to the grounding system
ISO 13297, Small craft — Electrical systems — Alternating and direct current installations, which is the standard that UK leisure craft should comply with requires that the ac system is bonded to the hull of a steel boat, or for non steel boats to the external grounding plate. The same applies for conductive cabinets of electrical equipment.
Ok thank you. So if i have this correct i need to run a wire from the inverters earth lug straight down to a ground point . ( ground plater or bonding system )
And the same from the earth out of the consumer unit
