I wish to ground my backyard solar shed, which will have a 130 watt
solar panel, 25 amp charge controller, two 12V-126amp hour deep-cycle
batteries in parallel, 1750 watt inverter, and AC distribution panel.
The system will have a nominal voltage of 12 volts.

First, do all of the metal devices I've mentioned above need to be
grounded separately to a single grounding point, or can a grounding
wire simply "daisy-chain" all the devices, and then terminate in a
single spot? This sounds like a stupid question even to me, but I just
need to know.

Second, once a single grounding point is reached, what is the best
diameter of copper grounding wire to use as a grounding conductor from
that point to the grounding electrode in the earth? And, must the
conducting wire be solid, or can it be stranded?

Thirdly, is there a requirement for the distance that the grounding
electrode must be away from the shed before I bury it?

Lastly, if I am only able to get the grounding electrode part way into
the earth, say 4 feet, can I put another grounding electrode 4 feet in
the ground some distance from the first one? If so, how far do I need
to separate the two grounding electrodes? Or, am I jst pipe-dreaming?

Thanks,
Lou Dalessandro

"arthuritis" wrote in message
ups.com...
I wish to ground my backyard solar shed, which will have a 130 watt
solar panel, 25 amp charge controller, two 12V-126amp hour deep-cycle
batteries in parallel, 1750 watt inverter, and AC distribution panel.
The system will have a nominal voltage of 12 volts.

First, do all of the metal devices I've mentioned above need to be
grounded separately to a single grounding point, or can a grounding
wire simply "daisy-chain" all the devices, and then terminate in a
single spot? This sounds like a stupid question even to me, but I just
need to know.

Second, once a single grounding point is reached, what is the best
diameter of copper grounding wire to use as a grounding conductor from
that point to the grounding electrode in the earth? And, must the
conducting wire be solid, or can it be stranded?

Thirdly, is there a requirement for the distance that the grounding
electrode must be away from the shed before I bury it?

Lastly, if I am only able to get the grounding electrode part way into
the earth, say 4 feet, can I put another grounding electrode 4 feet in
the ground some distance from the first one? If so, how far do I need
to separate the two grounding electrodes? Or, am I jst pipe-dreaming?

Thanks,
Lou Dalessandro


So many questions on such an elaborate project! Without doing a lot of
homework myself, I can't answer everything. There are, however, many online
resources available for you to research. I suggest that you get an
electrical code book (NFPA 70) for starters. Look at articles 480, 250, and
690. The solar panel and inverter manufacturers should also have
information available.

The main grounding conductor can be solid or stranded and is usually no
smaller than #8, but the code book can tell you better in your situation.
Two four foot ground rods do not equal one eight foot ground rod in terms of
code compliance. Rent a jack hammer and pound those suckers in. You should
have two eight footers. As far as distance you can have one right beneath
your electrical panel, but the second one must be at least six feet away
from the first although the optimum distance is sixteen feet. There are
other choices for grounding electrodes which are defined in article 250.

Normally an equipment grounding conductor is daisy chained since it is not
usually a current carrying conductor. I would check the code book and with
your local inspector on grounding since there will be AC and DC involved.


John Grabowski
http://www.mrelectrician.tv

arthuritis wrote:
I wish to ground my backyard solar shed, which will have a 130 watt
solar panel, 25 amp charge controller, two 12V-126amp hour deep-cycle
batteries in parallel, 1750 watt inverter, and AC distribution panel.
The system will have a nominal voltage of 12 volts.

First, do all of the metal devices I've mentioned above need to be
grounded separately to a single grounding point, or can a grounding
wire simply "daisy-chain" all the devices, and then terminate in a
single spot? This sounds like a stupid question even to me, but I just
need to know.

Electrical devices can be daisy chained. Electronic systems benefit
from single point grounds.

Second, once a single grounding point is reached, what is the best
diameter of copper grounding wire to use as a grounding conductor from
that point to the grounding electrode in the earth? And, must the
conducting wire be solid, or can it be stranded?

#6, solid or stranded.

Thirdly, is there a requirement for the distance that the grounding
electrode must be away from the shed before I bury it?

No.

Lastly, if I am only able to get the grounding electrode part way into
the earth, say 4 feet, can I put another grounding electrode 4 feet in
the ground some distance from the first one? If so, how far do I need
to separate the two grounding electrodes? Or, am I jst pipe-dreaming?

It's not the length of the rod that's important - it's the conductivity
of the soil. An 8 ft rod is average for average soil. But in some
soils a 4 ft rod may be adequate. Or if the soil is sandy or poor you
may need multiple 8 ft. rods. You are looking for 5 ohms or less
measured with an earth ground tester (not a standard ohm meter!). If
poor ground resistance is encountered, you need multiple rods or treat
the soil around the single rod with rock salt to increase conductivity.

Bob S.

"arthuritis" wrote in message
ups.com...
I wish to ground my backyard solar shed, which will have a 130 watt
solar panel, 25 amp charge controller, two 12V-126amp hour deep-cycle
batteries in parallel, 1750 watt inverter, and AC distribution panel.
The system will have a nominal voltage of 12 volts.


The 12V portion of the system does not require a safety ground as this
voltage is considered non lethal. It is advised to use one for the primary
reason of lightning protection and or unintentional connection to the 120V
side of the system.

There are strandard practices used by PV folks. Do some more research
before settling on a solution. The manuals of each piece of equipment
should have had something on the subject.


First, do all of the metal devices I've mentioned above need to be
grounded separately to a single grounding point, or can a grounding
wire simply "daisy-chain" all the devices, and then terminate in a
single spot? This sounds like a stupid question even to me, but I just
need to know.

Second, once a single grounding point is reached, what is the best
diameter of copper grounding wire to use as a grounding conductor from
that point to the grounding electrode in the earth? And, must the
conducting wire be solid, or can it be stranded?

Thirdly, is there a requirement for the distance that the grounding
electrode must be away from the shed before I bury it?

Lastly, if I am only able to get the grounding electrode part way into
the earth, say 4 feet, can I put another grounding electrode 4 feet in
the ground some distance from the first one? If so, how far do I need
to separate the two grounding electrodes? Or, am I jst pipe-dreaming?


Multiple Grounding electrodes and uthe use of a UFER (rebar in your
foundation) as a ground are all covered in NEC. Get a copy of Code Check
electrical (or another book) if you are doing any substantial wiring job and
want to be familiar with the principals and rules for safe wiring.







Thanks,
Lou Dalessandro

John Grabowski wrote:
"arthuritis" wrote in message
ups.com...

I wish to ground my backyard solar shed, which will have a 130 watt
solar panel, 25 amp charge controller, two 12V-126amp hour deep-cycle
batteries in parallel, 1750 watt inverter, and AC distribution panel.
The system will have a nominal voltage of 12 volts.

First, do all of the metal devices I've mentioned above need to be
grounded separately to a single grounding point, or can a grounding
wire simply "daisy-chain" all the devices, and then terminate in a
single spot? This sounds like a stupid question even to me, but I just
need to know.

Second, once a single grounding point is reached, what is the best
diameter of copper grounding wire to use as a grounding conductor from
that point to the grounding electrode in the earth? And, must the
conducting wire be solid, or can it be stranded?

Thirdly, is there a requirement for the distance that the grounding
electrode must be away from the shed before I bury it?

Lastly, if I am only able to get the grounding electrode part way into
the earth, say 4 feet, can I put another grounding electrode 4 feet in
the ground some distance from the first one? If so, how far do I need
to separate the two grounding electrodes? Or, am I jst pipe-dreaming?

Thanks,
Lou Dalessandro



So many questions on such an elaborate project! Without doing a lot of
homework myself, I can't answer everything. There are, however, many online
resources available for you to research. I suggest that you get an
electrical code book (NFPA 70) for starters. Look at articles 480, 250, and
690. The solar panel and inverter manufacturers should also have
information available.

The main grounding conductor can be solid or stranded and is usually no
smaller than #8, but the code book can tell you better in your situation.
Two four foot ground rods do not equal one eight foot ground rod in terms of
code compliance. Rent a jack hammer and pound those suckers in. You should
have two eight footers. As far as distance you can have one right beneath
your electrical panel, but the second one must be at least six feet away
from the first although the optimum distance is sixteen feet. There are
other choices for grounding electrodes which are defined in article 250.

Normally an equipment grounding conductor is daisy chained since it is not
usually a current carrying conductor. I would check the code book and with
your local inspector on grounding since there will be AC and DC involved.


John Grabowski
http://www.mrelectrician.tv

many places are no longer allowing daisy chaining of grounds.

Best to home run ground anyway to be safe.

With $$ you are spending be sure to add lightning protection to the system.
The solar cells make an inviting target for lightning.


"arthuritis" wrote in message
ups.com...
I wish to ground my backyard solar shed, which will have a 130 watt
solar panel, 25 amp charge controller, two 12V-126amp hour deep-cycle
batteries in parallel, 1750 watt inverter, and AC distribution panel.
The system will have a nominal voltage of 12 volts.

First, do all of the metal devices I've mentioned above need to be
grounded separately to a single grounding point, or can a grounding
wire simply "daisy-chain" all the devices, and then terminate in a
single spot? This sounds like a stupid question even to me, but I just
need to know.

Second, once a single grounding point is reached, what is the best
diameter of copper grounding wire to use as a grounding conductor from
that point to the grounding electrode in the earth? And, must the
conducting wire be solid, or can it be stranded?

Thirdly, is there a requirement for the distance that the grounding
electrode must be away from the shed before I bury it?

Lastly, if I am only able to get the grounding electrode part way into
the earth, say 4 feet, can I put another grounding electrode 4 feet in
the ground some distance from the first one? If so, how far do I need
to separate the two grounding electrodes? Or, am I jst pipe-dreaming?

Thanks,
Lou Dalessandro