Fine-tuning lighting and electrical- 50x80x14

[13mo]

I will be building a 50x80x14 machine shed in the next few months. I have a reasonable idea of what I will have done for this but I would like some feedback before actual work starts.

The building will be a 50x80x14 pole barn with a concrete floor with a vapor barrier underneath, and condensation barrier on the inside of the sheathing. Trusses 4' on center and poles 8' on center, and rafters will be open to below. There will be four 16x12 overhead doors and a man door on one sidewall, no windows, and no HVAC or plumbing inside the building, and nothing on the other sidewall or either end wall. Garage doors will be on electric openers.

This will be located on rural farmland. According to the contractors I have bid the project with, utility power will nearly certainly be a 320/400 A single-phase service that comes in overhead to a pole-mounted transformer sitting between the house and the building. The meter base will have multiple disconnects and one of the feeders from the meter base will go to the outbuilding, and the feeders from the meter base to the house and building will be buried.

I will be using the building for equipment storage (mainly hay equipment) and maintenance. The first project I will do in the building other than put the hay equipment in there will be to restore my family's 1965 John Deere 110 but larger projects will follow. I will have a good-sized air compressor and welder in the future which will go in the outbuilding. Anything else I could think to use there for tools would 20 amps or less on 240 volts, such as my pedestal grinder or a bandsaw, or 120 volt hand tools.

My thoughts are:

1. 100 amp service to the outbuilding. I did a guesstimate load calc with a 7.5 hp air compressor, 50 amp welder, and fluorescent lighting to give a worst-case scenario and the draw was right at 100 amps. I'd use a 20-24 space panel to make sure to have enough circuits. Any feedback on this?

2. Lighting to the typical ~90 fc range so I can see well. I did quite a bit of reading of this forum and played with the Visual 3D tool and came up with three options:

- 12k lumen 2' linear LED highbays (such as Lithonia IBE), 7x6 arrangement, 4' in from each end and then every third rafter (12') in between and six per rafter. This would be wired to two 120 volt 20 amp circuits.

- 15k lumen 2' linear LED highbays, 7x5 arrangement identical to above but one fewer fixture per rafter. Would be wired similarly.

- 6-lamp T8 highbays (e.g. Lithonia IBZ), 7x6 arrangement identical to the 12k lm LED setup. These would be using linear LED bulbs.

The questions I have are:
a) Are the 12k lumen or 15k lumen fixtures better for this application with a ~14' mounting height? 14' seems to be in a gray area where there doesn't seem to be a clear recommendation as to which one is better.

b) Are the integrated LED fixtures or replaceable-bulb linear LED fixtures recommended? I am a little leery of getting an integrated LED fixture because if something fails, the entire fixture must be replaced and it would be very likely that whatever new fixture is available at the time would be dissimilar to the ones already in use. I did a bunch of reading on this topic and nobody ever seemed to answer the question.


3. I will have outdoor lights over the overhead doors. I would like to have this on a switch controlled inside of the house so I can see to go outside there in the dark but not have the place lit up every night using a dusk to dawn light/lights. Since the building will nearly certainly be supplied from the pole rather than being a subpanel from the house, would it be worthwhile to do this the conventional way of running a conduit to the house for a separate outdoor lighting circuit or would another means such as a remote-controlled switch be better, and if so, which one?

Thank you for your input.

 

[cybrdyke]

b) Are the integrated LED fixtures or replaceable-bulb linear LED fixtures recommended? I am a little leery of getting an integrated LED fixture because if something fails, the entire fixture must be replaced and it would be very likely that whatever new fixture is available at the time would be dissimilar to the ones already in use. I did a bunch of reading on this topic and nobody ever seemed to answer the question.

I dont use tubes in a new installation like this one for a few reasons. Mostly it's because of longevity. For instance, the lithonia fixture you referenced will likely last twice as long as LED tubes. At 4000 hours of operation per year, it's rated well over 25 years. I think that eliminates your concern of replacements being available. To get 12,000 lumen fixtures from standard 2000 lumen LED tubes, you would need a 6 lamp fixture. That's over 240 tubes in total. That's a lot of possible failure points. Fixtures have built in dimming that's very easy to connect. Tubes have none. Fixtures are easier to install (again, try twisting in 240 tubes over head). And those are just some of the reasons.
CD

 

[13mo]

I see that the average lifespan of the LEDs is rated at the number of hours before they drop below 70% of initial lumen output. This is 100,000 hours on the better integrated fixtures and about 50,000 hours on LED tubular bulbs. My concern is not so much about this but about early death of the LEDs and drivers. I have been replacing conventional incandescent or halogen E26 bulbs in my current house with LED bulbs when they burn out. I've installed about 30 of the E26 LEDs thus far and have had three fail early, one had a driver problem where it flickered on and off sporadically and the other two had some of the LEDs in the bulb stop working. These were installed in appropriate fixtures for the types of bulbs used. Do reasonable quality integrated fixtures have the same kind of early failure problems?

I do realize that it would take 252 bulbs for six-bulb highbays. If these have a typical 50,000 hour lifespan, it would be mostly an up-front time issue with installation with occasional replacement of individual bulbs if they fail early. I'd be OK with that if it saves me from having to replace fixtures.

 

[ycgoat]

If it was me I would be more traditional with HIDs offset with tube fixtures, and use a long range wireless relay to switch some lights from the house.

If you are already anticipating 100 amp load you will want more for unforeseen usage and to lessen the strain on your service equipment.


Sent from my iPhone using Tapatalk

 

[cybrdyke]

No, it's not normal for quality LED fixtures to exhibit 10% failure rate like your E26's. In fact, it's not even normal for quality E26's. The industry failure rate from quality manufacturers is much less than 1%. From **** manufacturers, it's pretty high.
L70 can be deceiving, so be careful with those comparisons, especially with the **** manufacturers. When they say 50,000 hours, without documentation, then they mean 50,000 hours until full death, not 70%. Big difference. And there's a lot of ways to get to 70%. It's not necessarily a straight line drop off.

I dont really give credibility to the "one fixture will look different" notion. First, it's not likely to happen. Second, if it does, it will be a minute difference and you will be the only one who can tell and you can only tell when the lights are off. Third, it wont be for many years, because you'll likely be able to get the Lithonia for a long time. And, trust me, maintaining 250 tubes at end of life isn't nearly as easy as replacing a fixture.
Good luck,
CD

 

[13mo]

@ycgoat
Do you have a recommendation for a wireless-relay switch that would work for this usage?

I figured 100 amps as a worst-case scenario as only I will be working out there. Thus only one tool plus lights and something that could run automatically like an air compressor would be my maximum load. I will make sure to calculate the voltage drop to size the feeder wire correctly.

I think I'd go with LEDs on this one. Metal halides look neat and work fine when they're warmed up but take 5-10 minutes to warm up. Places I've worked that had them turned them on at opening and off at closing and never touched them in between. I anticipate popping in and out of the outbuilding for 30 seconds to grab a tool or something and then going back outside with some regularity. We often did have a few incandescent or fluorescent fixtures to provide a tiny amount of light to see by to go to the switch panel to turn the MHs on and off at past jobs, but that's a complicated workaround compared to just needing one kind of fixture that turns on at full brightness immediately.

@cybrdyke
The bulbs that had given issue were either Sylvania/Osram or GE as those are the name brands carried locally. I don't buy the cheap house brand stuff or worse, the noname Chinese knockoff stuff from online. The power in my current location blips a lot, probably due to being at the very edge of the utility's distribution network. The place I am building has a different utility and the service drop will be from one of their major 3-phase lines running along my property line, so hopefully fewer blips.

I just picked on that Lithonia fixture as it is carried locally and its information was available in the Visual 3D program. If there is something else reasonable you'd recommend, please do so. The two local electrical supply houses carry the entire catalog of Eaton and Acuity electrical products and the local big box stores can get most Metalux and Lithonia parts by special order if they are not in stock.

I suppose my last question here is would you recommend the 12k or 15k lumen fixtures?