Better explained....

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sparky723

Senior Member
Location
Haskell,Tx
Hey guys I need a little guidance here.
Ok, Here goe's..:grin:
I have a church that has several large HPS lights all around their property and it is costing them $165 a month. They asked me to see if I could find some lights to install so that the large HPS lights could be turned off/taken down. All but 2 are blocked the church building by low trees. (The HPS lights are on POCO poles approx 25' in the air.
After surveying all the locations where they want light, and is supposed to lit by these blocked lights, I noticed everywhere except 1 main location already has non working simple floodlights that can EASILY be replaced with some nice square quartz halogens to light up those smaller areas.
The "main" area I am speaking of is the main parking lot on the side of the gymnasium and annex (fellowship hall) buildings. The lot is 150' x 75'. Obviously, 1 long side of the lot goes along the side of the gym/annex; and the other 'long side' goes along a street.I will be mounting the lights on the side of the gym and have them shining on the lot about 15'-20' high. My question(s) to the forum is this: 1) Which light size (compact, medium,large) and type (MH or HPS) would you use on the gym building?
2) If you changed the smaller area lights from the simple floodlights to something other than square quartz halogen (HD/Lowe's) type; then what would you choose?
The reason I am asking in such detail is this: the church wants to spend less per month, but they also want to use these lights for 2 purposes..general illumination (Sundays/Wednesdays) and security (7 days a week) , hence photocells I plan on installing. I spent nearly an hour uploading and trying to get pics. on here of the church parking lot to help ya'll visualize the lot. If you would like me to email you the pics, PM me your email address. Thanks, sparky723 :rolleyes:
 

peter d

Senior Member
Location
New England
HPS is the best choice for energy efficiency (lumens/watt - gross light output for least amount of wattage) and lamp life (24,000 hours.) The major drawback to HPS is color rendering. This is generally not a concern for security applications, which is why it's so common for street and perimeter lighting.

The runner up would be ceramic or pulse start metal halide if color rendering is an issue. Lamp life is less than HPS as well as lumen per watt, so maintenance costs will be higher with MH.

I would use HPS for any outdoor security application unless the color rendering is an issue.
 

sparky723

Senior Member
Location
Haskell,Tx
Pictures...finally!!!

Pictures...finally!!!

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting002-1.jpg

The black arrow shows the only HPS light on a pole approx 25' up lighting the parking lot. In this pic. you can also see the gym that will have 2 (or 3) lights mounted to it.

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting001-1.jpg

This is the annex building next to the gym. It makes up the rest of the parking lot. The 2 red arrows point to 2 of those HPS lights monted on another pole BEHIND the annex building. When the 2 lights are on, 1 shines on another lot behind this building, and the other lights the playground also behind this building. NO light from either of these HPS fixtures hits the parking lot in front of the gym/annex buildings.

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting005.jpg

This is a close up of the side door of the gym (activity buiding). You can see a guard light mounted above the door. It is 14' 6' up and it is a 175 MV light. 120v. It is switched just inside the door and I felt it would be a good place to catch my power.

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting018.jpg

This is a shot at night from the door of the gym facing forward with only the HPS light on the pole on.

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting021-1.jpg

This shot shows the annex building with the HPS light on (far left, off picture) and the 500w quartz light (prevuiously mounted) and pole mounted HPS light behind the annex that lights the playground. The white arrow points to the 500w quartz and the red arrow points to the HPS light.

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting020.jpg

This shot is from the gym side door looking left with the 500w quartz light on showing how well it lights up that section of the parking lot. I am thinking of leaving this light (unless someone has a better suggestion) and mounting the 2 (or 3) lights on the gym.

http://i254.photobucket.com/albums/hh108/jacywest/ChurchLighting010.jpg

This shot is from across the street with only the HPS in the corner turned on. You can see how the lot is so dark.

I took pictures of the 175 MV light above the side gym door turned on at night, but choose not to include those pix since I will be demoing that light anyway.
I hope this gives EVERYONE a much better visualization of what I am working with.

I will be anxious to hear respones and suggestions from this forum. Thanks for your time. sparky723:wink:
 

nakulak

Senior Member
I think you should check the wattage on the sodiums and maybe even amprobe them. I agree with above - they will probably end up spending more if you plan on adequately illiuminating the space with halogens.
 

peter d

Senior Member
Location
New England
sparky723 said:
I will be anxious to hear respones and suggestions from this forum. Thanks for your time. sparky723:wink:

I would take down the MV barn light and the quartz light and deposit them in the nearest dumpster. I would replace them with a decent commercial grade HPS wall pack or floodlight.
 

B4T

Senior Member
HPS.. not what it seems

HPS.. not what it seems

I installed (5) 150 watt wall packs and blew the 15 amp circuit.. I checked with an Amprobe and found out each wall pack was using 500 watts. Further checking, I found out it was a low power factot ballast.. hight power factor ballast use less than 2 amps each.
 

iwire

Moderator
Staff member
Location
Massachusetts
All ballasted fixtures use more power then the total of the lamps and the NEC requires the circuit to be sized based on the ballast current ratings not the lamps.
 

peter d

Senior Member
Location
New England
BLACK4TRUCK said:
I installed (5) 150 watt wall packs and blew the 15 amp circuit.. I checked with an Amprobe and found out each wall pack was using 500 watts. Further checking, I found out it was a low power factot ballast.. hight power factor ballast use less than 2 amps each.

The only way you can get an accurate reading of the real power being consumed is with a true RMS amp meter.

However as Bob said you must size the circuit based on the rated current, which in the case of a low power factor ballast is the apparent power rating, not the true power.
 

peter d

Senior Member
Location
New England
BLACK4TRUCK said:
the problem was the idea of 150 HPS being energy saving.. IF I used the right fixture, I would of been ok

HPS is energy saving. It's just that the cheap lights generally don't have the PF correction capacitor built in so the end result is that you can't put as many lights on a circuit as one with PF correction built in.
 

jeremysterling

Senior Member
Location
Austin, TX
I like the metal halide lums, pulse start if available. 175W should be OK. If you change the CKT to 240V be sure to get 240V photocells.

Also, I think it is a nice gesture to consider the neighboring property. Will your lum placements create a nuisance to neighbors?
 

kingpb

Senior Member
Location
SE USA as far as you can go
Occupation
Engineer, Registered
You may want to seriously look at the cost for replacing the fixtures, installation, etc., and the differential in energy savings. You may find that the pay back period is greater than the life expectancy of the current fixtures. Meaning it may be more prudent to leave them until they have to replaced with new ones. Trimming trees, and possibly turning a couple off may be a wiser choice.
 

Jraef

Moderator, OTD
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Lighting is about lumens at the "work surface". There is no better cost-per-lumen type of lighting than HPS. Anything you do will cost you a LOT more. So start off by defining your tasks. Are you being asked to reduce the lighting cost? If so, jettison the MV and quartz lights immediately. Reassess the lighting task. If the MV light is intended to light up just the doorway, a CF fixture is usually adequate for that. But if it is supposed to light up a wide area, replace it with another HPS fixture. An HPS with an equivalent lumen output to a 175W MV lamp is about 40W, so there is 135W of savings right there.

Here is a rough guide:
Halogen (Quartz) = 15 lumens/watt
Regular Incandescent = 17 lumens/watt
Mercury Vapor = 24.5 lumens/watt
T8 Fluorescent = 48 lumens/watt
Compact Fluorescent = 61 lumens/watt
Metal Halide = 80 lumens/watt
High Pressure Sodium = 105 lumens/watt

So HPS is the BEST use of your energy dollars.
MH is better if, as mentioned earlier, color retention is important.
CF is low cost and decent output, but the lumens don't travel well over distance (difficult to focus).
MV is just plain bad all around, but it is cheap to purchase.
Halogen is good only if you need a lot of light temporarily from a compact fixture. It is the WORST choice for permanent area lighting.

PS: LED lamps, best available, are good for about 75 lumens/watt, making it close to MH in terms of efficiency and color, however their cost is still extreme for large area lighting. But their best claim-to-fame is life span.
 
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Mr. Bill

Senior Member
Location
Michigan
Jraef said:
Here is a rough guide:
Halogen (Quartz) = 15 lumens/watt
Regular Incandescent = 17 lumens/watt
Mercury Vapor = 24.5 lumens/watt
T8 Fluorescent = 48 lumens/watt
Compact Fluorescent = 61 lumens/watt
Metal Halide = 80 lumens/watt
High Pressure Sodium = 105 lumens/watt
I've got some issues with you're guide above.
Mostly that your T8 lamp is about half the efficacy it should be.

From my own excel file that I made from catalog information. All of my numbers are based on maintained lumens since that is what I design to. Max lamp wattage is 400 because I don't use anything larger.
T8 Fluorescent = 77-90 lum/W
T5 Fluorescent = 78-87 lum/W
T5HO Fluorescent = 67-73 lum/W
Compact Fluorescent = 52-66 lum/W
Metal Halide = 27-52 lum/W
Pulse Start MH = 30-73 lum/W
Ceramic MH = 48-60 lum/W
High Pressure Sodium = 51-87 lum/W
Induction = 51-58 lum/W
Incandescent = 11-14 lum/W
Halogen = 18-21 lum/W
LED is anywhere from 20-60 for commodity. Brand matters. Good luck getting information on this when you buy it.
 
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