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MDKing
03-16-2007, 11:11 AM
For those of you with outdoor haunts, have any of you had someone come in to have the power grounded? If so, could you share a little about it? What's the costs, lead time, and any pros and cons with doing this? We use large generators and it can be very expensive both with rental and especailly fuel expenses. Any info or experiences with this would be greatly appreciated.

Thanks
Allan

imax
03-16-2007, 02:07 PM
Allan,

We've used giant generators at the haunt for years now. These generators are grounded by default, and the people you rent them from should provide a technician to help you hook it up properly. If not, you should rent from someone else.

Your circuits need to be GFCI'd at the first outlet. Many times the panels already have these available at the breaker, but make sure you ask.

Make sure you use cords that are UL approved for outdoor use, and outdoor splitters. NEVER use an indoor power strip (or any indoor cord). Your local inspectors and whatnot shouldn't have any problems with your wiring as long as you are using cords approved for that purpose.

Make sure your wiring is not customer accessible, and make sure it doesn't cross any footpaths, doorjambs, etc where it could be damaged.

Inspect every foot of your cords each year. Throw away any that are nicked, cut or otherwise damaged.

Consider moving to LED-based lighting. It's cheaper, low voltage, and easy to battery-backup. A lot of other things can be moved to low-voltage as well, like air valves, prop controllers, etc.

Finally, if you are renting power generators, contact your local power company and see how much it would cost to drop a hard line to your property. In our case, it was less than 1 seasons worth of generator rental, including having an electrician come out and hook up our panel, plus a shed to put it all in. If you are working in non-freezing weather, they can usually get everything done in about a month.

-- I

Karl Fields
03-16-2007, 02:57 PM
Alan,
We have used large generators for years, but in 2006 our electrical inspector made us ground the generator! Mind you, this is a 110KW, 5,000 pound beast! We ended up driving an 8' (1/2"?) copper clad ground rod next to the generator and then bonding that (used maybe #8 copper?) to the ground lug on the generator's hookup panel. PITA but the inspector liked it. Cost < $25.00

MDKing
03-16-2007, 03:54 PM
Thanks Guys!

Karl, I was hoping to hear from you, I'm going to email you soon about something else too, if you don't mind?

As for grounding the power with the copper pole, we have always had to do that here. I have heard that the electrical company can come out and ground power to their source, so we would just be billed through them as opposed to generator and fule expenses...Have you considered this?


Imax, so you had your power company do this? I'm assuming it was in the $2500-$3000 price range to do this? Also, how far in advance did you have to contact them?

Thanks,
Allan

Karl Fields
03-16-2007, 08:48 PM
Sorry, I misunderstood the question!
The last time I looked into a temporary power drop, they had a limit of about 2-300 feet from a transformer to our service panel. We are like 1000' feet and a railroad track away from the nearest transformer, so generators are still in my future.

Jim Warfield
03-17-2007, 12:37 AM
Never substitute the ground that travels in with your hot lines for just a wire connected to a metal point driven into the earth.
Some devices will run for awhile wired like this but then things begin to burn out, very pre-maturely.
I heard a guy was wiring heat pumps like this and he junked many compressors, they ran for awhile, though!

MDKing
03-17-2007, 09:01 AM
No problem Karl. I know all to well about the generators as well.

Jim, I could see where that would be risky too. Las tthing I would want is to burn our compressors in the middle of the show with no more back ups!!

Allan

imax
03-19-2007, 07:32 AM
Yes, we contacted the local power company.

We had about a 800 foot run from the nearest distribution pole (not all poles are distribution lines!), and needed to have them run a line for us to an in-ground transformer. We had two options, either via overhead lines or an underground line.

Overhead lines were going to be about $1.75 per foot to run, plus pole costs (needed 3 of em) @ $250/ea.

Underground lines were going to be about $5.75 per foot.

So, overhead were less expensive, BUT, the poles were going to need to be in horrible places, and it's unsightly at best for our location.

And, underground was going to put us just over budget.

So, we asked if we could do overhead for a while, and then do the last few hundred feet underground. He didn't want to bring two crews out to do that, so the company gave us a discount if we did it all underground.

Total cost for the electric drop (underground) from the power company: ~3500.00

We then had to have an electrician come out and install a panel into our shed, with GFCI outlets and a grounding rod and all that jazz. And, we had to build the shed to put it in, and that cost a couple hundred bucks.

So, all in all, we break even this year, spending about 6K on our electric. But, we were spending nearly that on the generator rental alone each year, not including the cost of fuel, maintenance on the small generators we used in the off season, and time lost going on 'gas runs', or time gained by having full power all year... well, it's money well spent. Next year, we won't incur any of those installation costs, so electric for the whole year will be far less.

As far as time frame, I'd say call your power company and get an engineer out to do a site survey. Depending on how busy they are, it can be done pretty quickly. They did our entire drop in one day, but there was a few weeks lead-time because they had other customers to install. Winter was coming fast, and a lot of people were scheduled to get power drops before the ground froze.

IF we had known what we were doing, we could have sped up the process a bit. Have your electrician come out and do the panel, even if you are waiting for the power company. He will put in everything up to and including the meter socket. Get your inspectors out to check his work and get approval on it. Then, the power company guys can just plug you in. We screwed up a bit because we didn't know that they pretty much worked independently of each other, so they can work at the same time.

So, I hope this helps. Let me know if you have any more questions.

-- I

MDKing
03-19-2007, 09:58 AM
Imax,

Thanks for all the helpful tips, it gives me a lot to work with. One more question though, approx. how much was you electric bill for running power for the season to the power company?

Thanks so much,
Allan

imax
03-19-2007, 10:08 AM
No idea, haven't had a season with it yet. I expect it to be pretty low, as we only run Friday/Sat/Sun in october. I suspect September's bill will be higher, since we are working on it a lot.

We really only need the 110VAC for a few parts in our haunt:
- Air compressor
- Audio amplification
- Computers
- Ticket Booth ops
- Vortex Tunnel motor
- Parking lighting
- Charging 12v batteries

The rest of our show is run on 12VDC, so our electric needs are pretty slim.

-- I

MDKing
03-19-2007, 03:28 PM
Sounds good Imax! Again, thanks for all the info you shared!

Allan

imax
03-19-2007, 03:32 PM
No problem, good luck!