To Ground or Not to Ground... OK Bond, Reference, etc.

[Randaltb]

Greetings all!
Currently I am running 12 ~83 volt panels on two classic 150s tied to one 24 volt AGM battery bank.
I have not tied the PV or Battery (-) to chassis/earth.

Is there any advantage (Or disaster) related to tying the battery and PV (-) to Earth/Common/Chassis?
** It seems redundant if the Classics are already tied to the same (-) as the batteries (Output side) and panels (Input side).
    Also the Inverters are also using the same battery (-)

Maybe I am missing the point?
F.Y.I. My system is in a steel container so it would be easy to reference all (-) to the same point, just not shut its a good plan...

[tecnodave]

Randaltb,

Welcome to the forum!

Yes do ground your system for many reasons.  First off the Classic is not grounded internally. It can be used in a positive grounded system. So a ground reference must be made somewhere. If lighting were to strike any part of solar array the whole system would be at that voltage above ground!  Extreme shock hazard as lighting is about 1,000,000 volts per 10 feet of strike distance.  Even if you are not in a lighting strike area static voltage can be built up in the system such that the whole system will float at hundreds of volts above ground.  So absolutely do ground your system.......not knowing enough about your system I will suggest a heavy bond cable from your battery negative directly to the frame of that steel storage container.  And then I would look at how that container is grounded.  If you are going to have an inspector view your system you will need a standard home ground rod tying that container to ground..........yeah 8 by 40 foot steel container does have a large ground contact area but you cannot depend on that being a ground!   Depends on ground resistance.   Minimum requirements are a 8 foot by 1/2" diameter ground rod driven in flush to ground level with only about 3" exposed with minimum 6 ga. Copper wire bonding cable connected to the framework of that steel container. Personally my ground bond is 4/0 welding cable connected to an array of 4 ground rods. Overkill ! But to be sure I am bonded!  Lighting is nasty stuff......I've been doing electricity for 50 years and more and I do live work for a living but I am fearful of lighting.   One million volts will only jump 10 feet! (Unless there is ionization of the atmosphere caused by that lighting, in that case it will jump even farther than that)
So we are really dealing with some scary stuff there.

So to protect yourself, others, AND your solar system  DO BOND!  Post more detail and one of us will help you out with your system!

David