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I'm looking to install some new 4 foot 4 bulb T5HO fixtures in my garage and I've noticed that the balasts say that they can be wired with either 110V or 220V. My question is, is there any benefit to wiring them up in 220? The downside to me seems like it is a lot more work and extra materials/wires to run an extra hot to every light fixture in the 220V configuration. Is there a reason why anyone would choose to run the lights in 220V?
Thanks,
Royce M
Royce:
Extra wiring? I disagree... two-pole breaker with two hot wires and ground to each fixture (220V) or single pole breaker and one hot wire and one neutral and ground to each fixture (110V)... so the wiring is similar until you connect a lot of fixtures...
Advantages are when you are installing many fixtures... in your case with 54W T5HO you can get a max of 8 fixtures to a 20 ampere circuit. At 220V you can connect twice as many per circuit. Another advantage is voltage drop is reduced with the higher voltage that will allow longer circuit lengths without increasing wire size...
If your garage is large (more than 8 fixtures!) you may wish to consider it...
In my case I'm looking at 6 fixtures (4 bulb in each fixture) but I'm still interested in learning which is the more efficient way.
This might be a very basic question but in wiring a 220V light fixture, is the neutral not needed? That is why I thought I would be using 1 more line of copper.
One other question is you mentioned 8 fixtures max at 110 on a 20A circuit. At 54W per bulb and 4 bulbs per fixture and 8 fixtures on a 110V circuit I got 15.7A theoretical. Should I be adding a buffer so as not to max each circuit out.
At what range of lengths (ballpark) should I start to worry about voltage drop to where I should start plus sizing the wires?
Thanks for all your help. Sorry for so many question.
Royce M
Royce:
1. Not a problem... with most 220V equipment as in light fixtures, the neutral is not used.
2. The maximum continuous load allowed by the electrical code is 80% which in the case of a 20 ampere circuit is 16 amperes... so 15.7 is OK.
3. If you're going less than 50 feet I wouldn't worry... actually at a 16 ampere load the maximum recommended cable length would be 56 feet with a 3% voltage drop.
Of course if you wire these lights with 220V you can go twice as far... the drop is linear.
If this garage is attached to a dwelling, the maximum voltage allowed to be used is 120 volts.
If this is separate structure, then it may be allowed to be considered as a commercial garage, and 240 volts is allowed.
To size the circuit, you do not add the wattage of the lamps. You read the input watts or amps listed on the ballast, and size the circuit from there.
See attached product datasheet, a typical 4 lamp T5 HO ballast draws 240 watts and 2 amps at 120 volts and 234 watts and .86 amps at 277 volts:
http://www.advance.philips.com/docum...O-7600-B_F.pdf
F54T5/HO 120-277 Centium # ICN-4S54-2LS-H 240-234 1.00 2.00-0.86
The advantage using a higher voltage allows more load on a circuit, and results in copper and labor savings.
Does not change the load in wattage, you still pay for the same amount of energy used , no matter the voltage used.
Tk...
I wasn't aware there was a voltage limitation in dwelling and similar occupancies, but here it is in NEC 210.6(A)(1)... thanks, learn something new everyday.
Yep, that's the tricky part. Even if a garage is detached from a dwelling, and looks like a standard residential garage, an inspector may still consider it as residential.
Thanks for all the feedback. I have a couple more questions I've been thinking about. So if I decide to go with 240Volts to wire the lights then am I correct in thinking that at each light I will have one 12 gauge black 120, one 12 gauge red 120, and one 12 gauge green for ground? No neutral needed. Additionally given the discussion above does is sound right that I can run all 16 light fixtures on a 20A circuit with all 12awg wires (black, red, and green)? At the light switch end of things is it just a standard one black in one black out or is there something special to accommodate for the 240V circuit?
Thanks again for all the help,
Royce M
The amp draw should be one amp per fixture, so 16 fixtures should fit on one circuit. I suggest using more that one circuit for these lights.
Correct, a neutral is not needed, however, you may use two wire cable plus ground with black and white, and tape the white a different color to indicate it is a hot wire.
Need to use a double pole switch, rated for 240 volts.
The lights I've chosen are Lithonia IBZ-454-WD. In looking at the specs online I noticed that they list it rated at 120V or 277V. This might sounds like a weird question but is 240V the same as 277V? Or is 277V achieved only in comercial applications? Will it be safe and efffecient to run these on a 240V residential service. For reference the garage is detached and I have a 400A panel running both the home and the garage. 200A to the home and 200A to the garage.
Thanks,
Royce M
The ballast is rated to handle any voltage from 120 through up to 277 volts, it will work fine on 240 volts.
Relating to the theoretical loads on my 200A panel when running the lights at 240V. If I understand correctly, I should be using a 20A double pole breaker. If I'm running 16 lights at 240V, assume 1A load per fixture, should I count that as 40A used of the 200A I have available? Hope that didn't sound like too much a riddle. Thanks again for the help.
Thanks,
Royce M
I doubt you have a 240v ballast. It's mostly likely a universal voltage ballast, meaning is operates at 120v single phase or 277v 3phase (480/277). If it were 240v it would have to have 3 leads for power, 1 for each hot leg and 1 for the neutral. I'm sure it doesn't. No 240 and 277 are not the same. But your ballast is 'smart' so you wire it the same. In your application you have to wire it 120v. Nice choice of fixture by the way. If you check with your local utility they probably have a rebate program and will pay you back for most of the fixture.
Oh, and as far as effenency they are the same if your talking about your electric bill. Using them for 1 hour at 120v at 2 amps uses the same amount of energy as 1 hour 240v 1 amp. But your ballast can't be wired at 240, only HID ballast are quad tap.
Thanks for the responses. I'm learning a lot. I'm also realizing there are a lot of details. One more thing. Maybe is sounds odd but I'm planning to wire up the lights in the ceiling but rather than hard wire them I would like to install 20A 120V recepticals in the ceiling for each light fixture. Is this OK to do? Are there any code violations prohibiting this? Being that each receptical is dedicated for each light fixture and that this is being in the garage, will I have to used GFCI recepticals in the ceiling?
Thanks,
Royce M
That's actually a very good and comom way yo wire them. Any supply house will have a 6' pre-wire appliance cord for a few bucks each. Cheaper and easier than making the whips yourself. I'm going to defer on the GFCI, I'd imagine you would, since a garage door opener now needs GFCI protection.
In the 2011 NEC they are required, 210.8(A)(2).
About $8 and a good idea...
277V is a three phase voltage, and it would be on one hot wire and would require a neutral. Not the same at all. And not available in Residential.
Those lamps are 54 Watts each, eight of them, even in a four car garage, will be realllllly bright, I don't think you need to do the 220V thing, those ballasts will consume the same power at whatever voltage you use. Use one 20A single pole space in your panel (cheaper, more room for other stuff) and save the expense of a two pole switch v. single pole. Also avoid inspector issues altogether
It is a residential garage but it is roughly 1800 sqft. Ceilings are 18ft on the high bay side and about 9ft in the workshop area. So far my plan is to run 120V to run the lights (parts recepticals, pigtails, etc. will cost less). I did speak with the tech rep at Philips regarding the balasts and according to him the balasts I received can be run on residential 120V, 240V, and 277V. For reference the balast is a Philips Optanium ICRP-4PSP54-90C.
Regarding GFCI, could I just use a GFCI breaker at the sub panel instead of an individual GFCI at each receptical?
Thanks,
Royce M
Oh and where are you able to find GFCI recepticals for $8. Everywhere around here I'm finding them at about $15 even in bulk. Any good online retailers?
A tamper proof GFCI should be $12 to $15. But you only need 1 per circuit.
How many circuits are you planning for the receptacles? Why not just line/load one GFCI at the beginning of each circuit? I would try going to a local electrical supply house and see how much they would charge for one.Quote:
Originally Posted by roycemek
I like Pass and Seymour/Le Grand
Specification Grade or tamper proof if needed
http://www.legrand.us/electrical-out...x#.UB2FSk1lRN-
And get good(at least commercial grade) U ground receptacles too, as long as you're doing a quality job
Those ballasts have a black and a white lead, you always connect the white to an incoming neutral with either 120 or 277 which both have a hot and a neutral, when connecting them to 240V the white lead just connects to L2 ( the second hot leg) there aren't 3 leadsQuote:
Originally Posted by mike 165278
http://www.platt.com/platt-electric-...px?zpid=853492Quote:
Originally Posted by roycemek
I prefer fixtures hard wired and mounted directly on the ceiling ( you may find this necessary if your garage doors are on tracks parallel to the ceiling) It gets them up a little higher and uses less hardware, one less top surface to collect dust too. These fixtures look like they have a full size can rather than some of the skeleton-y fixtures I've put up lately, should be simple to just screw them up over a round plaster ring?
Skeleton-y T5HO
http://www.e-conolight.com/pdf/SpecS...LF34X54U30.PDF
But they offer nice little cable hangers and are cheap, the last ones we got had ballasts made by Advance, which In my opinion is always the best ballast maker. We haven't had any callbacks yet with these fixtures, only been up for 2-3 years now, (new technology)
Well, new tech in that up until just a couple of years ago the ballasts offered weren't very good, made by fly-by-night brands you never heard of and broke down a lot. Frankly, I had no confidence in these (48" T5) until Advance Ballast Co. started making the ballasts for them. Little short T5 has been available for 20 years, but these big ones weren't really viable until the reliability problem got worked out about 3 years ago. Now we are using the 6 lamp ones where we used to put 250W Metal Halide fixtures
I'm planning 1 circuit for every 4 recepticals. Each receptical is dedicated exclusively for each light fixture. In total I'm planning 4 circuits. I will lay out the wall switches to turn on two fixtures at a time. The recepticals will be in the ceiling at 18ft high and if I'm interpreting the NEC code and the conversations correctly the GFCI test and reset needs to be easily accessible, I'm assuming the 18ft ceiling is not accessible? And are there no more exceptions in the 2011 NEC for GFCI? Humm. Maybe this might be easier and cheaper to hardwire the lights.
Thanks,
Royce M
Remember you are allowed to "line/load" a protected string of receptacles out of one GFCI, Seven on a 20A circuit, (180VA each for load calcs) the eighth one is the GFCI. A light fixture is a lighting outletQuote:
Originally Posted by roycemek
Two circuits would allow this.
Each circuit goes to GFCI recptacle on wall first, hot and neutral in on the LINE half, out on the LOAD half to the (first, if 3way) switch for half of the lights. This would require two separate duplex recepts, but why not one double duplex GFCI on the same wall near the switches? Feed two switches (each does two lights so 4 switches right?) out of each one of the GFCIs, the GFCI's will then be protecting each bank of 2 lights, where you can use regular 15A Uground receptacles instead of GFCIs
Note: manage your neutrals carefully when wiring this, keep them marked and separate
Hardwired always looks cleaner when done well and since they aren't receptacles they don't need all this GFCI arrangement, don't even need to be fed from a GFCI
The 18ft ceiling is "accessible" just not "readily accessible" since I assume you cannot fly... you're OK, but you don't care anyway because the set and reset buttons are over next to the door into the house... hunh?. unless you're hard wired, and then none of that stuff even applies to you.
Um, no. A ballast needs a neutral to work. I've never seen a 240v ballast for 4 lamp F54T5. If you have, I'm interested in checking it out.Quote:
Originally Posted by shuntripper
What are the dimensions of the room you are lighting up. Also what color walls and floor. I'll do the light calc for you. Also. Standard 4 lamp F54T5HO ballast draws just under 2 amps at 120v. You can comfortably put 8 fixtures on a circuit and still be under 80% of the circuit rating. I recommend you come out of the panel and wire a faceless GFCI in the wall of the garage. From there feed your lights (standard outlets). Depending where you live the outlets might need to be tamper resistant. The faceless GFCI will provide GFCI protection for the whole circuit, but not provide an outlet. And mounting it on the wall will make it easily accessible.
In total the dimensions are 50ft x 35ft. The side with the 17.5ft ceilings is 25ft x 35ft. The other side is 25ft x 35ft and ceiling height is 8ft. The IBZ-454-WD is for the high bay side. For the 8ft ceiling area I'm looking at the same IBZ's but in a T8. Plans for now I believe to have the walls and ceiling white and floor a concrete color. Thanks for all the help.
RE the GFCI's. Is it fine to just buy a 20A GFCI breaker and put that in my main panel and forgo the extra wiring box layout etc, for placing a blank GFCI somewhere on the wall. I checked and it looks like I can get a replacement 20A GFCI for around $50. Is cost usually the factor here are is there something else I should consider?
Thanks,
Royce M
Outlets in the ceiling for lighting do not require, and is not recommended to be GFI protected.
Royce, you need 6 fixtues for the larger area. That will give you 42 foot candles at 30". On the T8, are you going with 4 lamp or 6 lamp? Also are they 'super T8' or standard? A super T8 is more efficient, basically you are overdriving a T8 lamp to get more lumens, increasing efficiency.
You need to go look at one then, lots of ballasts have been wired this way for yearsQuote:
Originally Posted by mike 165278
I agree they aren't recommended, as far as required, I was just dinged on a recertification test for not counting a lighting receptacle in the ceiling of a garage as one that needed to be a GFCI.Quote:
Originally Posted by tkrussell
Of course Jade Learning could have been mistaken? I think their reasoning is that the light can be unplugged and an extension cord can be plugged into it.
Show me one. It's an electronic ballast. It needs a neutral. A fluorescent ballast rated at 120-277v does not mean it's quad tap (120, 208, 240, 277v). It means it is 120 OR 277v. That is it. No other voltage will work.Quote:
Originally Posted by shuntripper
OKQuote:
Originally Posted by mike 165278
http://www.ebay.com/itm/T5-High-Bay-4-Lamp-Fluorescent-HO-Electronic-Ballast-/220940136536#vi-content
Nope. The description says the fixture is a Howard Industries Fixture. Check Howards site. Below is a link to that fixture on Howards site, clearly saying on the lower left that the fixture is rated 120 OR 277V ONLY. Try again
http://www.howard-ind.com/HowardLigh...escent/HIB.pdf
Whatever, I'll concede your point. This is getting too much like pointless w---nie wagging and we don't need to irritate any moderatorsQuote:
Originally Posted by mike 165278
Thanks Mike. I really appreciate you doing some calcs for me.Quote:
Originally Posted by mike 165278
On the 8ft ceiling side I guess I haven't given as much research as I should have regarding T8's. I didn't know there was a super T8 and a standard. How can I tell the difference? Is there a wattage difference that designates a super T8 vs a standard T8? I'm looking at 4 lamp models. The model I am looking at is the Lithonia IBZ-432-WD.
Thanks,
Royce M
What are you using the space for? You can probably just use T8 tandum 8' open strip lights.Quote:
Originally Posted by roycemek
Mostly workshop. But a little of everything. Woodworking, mechanic work, machining, etc. Really nothing specific.
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