The orange "Romex" is #10, by the recent color codes I have seen. #14 is white, #12 is yellow, #10 is orange, black is #8 or #6, gray is for UF.
Edit: If you want to run in conduit you could run three #10, or three #12 THWN or XLPE insulated copper wires in 1/2 inch galvanized RIGID conduit, and you would only need to bury 6 inches deep. That's a shovel job. As far as I know, there's no depth requirement for data cables, but correct me if I'm wrong.
If you run the conductors to the observatory directly to a receptacle or receptacles, from a GFCI breaker in the garage box, I believe you would not need a ground rod at the observatory. That way, it's a branch circuit, not a feeder to a sub-panel.
There are some codes for low voltage/data, but would have to pull out the book to check, as they are generally uncared about.
I believe the OP's "electrician" is saying drive a ground rod(which should be driven vertical 8', not dropped flat 2 feet deep in a trench cause you're to lazy to drive it) in place of grounding back to main service. No no, as Rick and I pointed toward.
Its an area where the code is up to interpretation(as a lot of the book seems to be, have had two inspectors tell me two different things)
Arguments either way saying an earthen ground at a detached structure gives "potential" of this and that, vs. stopping something such as a lighting strike from making it back to the main house. No matter what should have that ground back to service entrance.
County I live in, detached garage, that feeder ground covers it. County I border where 90% of my work is, have to have a rebar(ufer) bond along with the ground in the feeder. If only one branch circuit feeding it, then no need. Two or more, rebar bond, even if its 2 separate circuits and not a sub. Ground rod wont cut it..
They also require a load calculation(as per code requirements), unlike the county I live in. Don't care if you wired a screened in porch on a 1500sq. ft. house with a 200 amp service. Gotta make sure your not overloading that service. Though I have had them let me slide a couple times.
But with that they get $25.25 to check my math and send me an email saying "your calculations have been approved based on the information you submitted", field inspector never sees it. And another $30.30 trip charge to swing through to look at clamp on rebar before concrete is poured. Why everything in even $ and cents? I asked one day. Cause they have to give the state their 1%..
Anyway, I'm ranting.
GFCI is fine at panel or at first receptacle at obs.
Someone cut corners to save a few dollars or save a short trip on that installation. They are using a bare wire for a neutral, and have taped a white to function as black (conductor), it appears. They should have run a 4 wire #10 cable, with black, red, white (neutral) and bare (gnd). It really should be redone, if possible, IMO.
Agree should be corrected, but how many houses/garages are out there with that installation for many years that are still standing? Plenty.. But should be corrected for the reasons NEC has them in place. No need to dig into the science, just do it has been determined for reason..
But you can re-identify a wire as a hot to use 2 wire for equipment that only requires 240v and a ground but no neutral.
When this subpanel was done years ago, it was done by a certified licensed electrician. I think at the time it was never imagined anything more than the minimal was going to be ran at or from the garage. When i go into the cellar I can see that its indeed 10/2 with a ground (says on the wire).
And this is the wiring inside the panel in the house:
So i'm trying to get a handle on what has been said so far here..
Only one grounding point should occur at the main point of the house with a copper rod correct? If so, then wouldnt it follow that a ground does go from the main panel to the garage (or is it being suggested the metal in the garage panel itself isnt grounded)? The thinking is that the ground is somehow acting as a neutral here? I cant imagine our original electrician would have done it this way and that issue with the 10/2 wiring that there is not a dedicated neutral (to the garage)?
Still also unclear on the whole electrical pvc and wiring, i was pretty sure the orange 10/2 was put in pvc, maybe not, its been awhile since that was run.
If that bar in your garage panel where the grounds and neutrals are hooked to does not have a screw contacting it to the enclosure(metal to metal) then you have an ungrounded enclosure. One thing is you could have a slit in the insulation on a "hot" wire that accidentally got cut and is in contact with the housing if it were bare metal, which some are, your're energizing a box that is just waiting for you.. Slim chance that you touch it while another part of you is grounded, then it's gonna get you! As long as your not barefoot in a puddle of water you'll likely survive.
The ground is being used as a neutral, which should be corrected.
To verify if it is piped, have someone watching where it comes into panel, and tug good on the other end at house.(of course shut down the main to be safe). If piped you should at likely at least see wire wiggle a little at the other end.
Oh, and as far as digging.. If you take a pass along with a round nose shovel, and then go deeper bit by bit in line with the trench with a trench shovel, you can be down 2' in easy ground "somewhat" easy..
Edited by spacemunkee, 20 July 2019 - 09:21 PM.