Flouresent lighting questions for the wizards

Ive got a shop 14' wide by 55' long
For years Ive had a series of 4' double tube florescent fixtures hanging and have had no issues with them.
The shop is unheated (California) but the winter temps do go down to the high 30s at night in the winter time on occasion. Ive had some lights have issues coming on at those temps in the past.
I scored a bunch of 8' (2 sets of (2) 4' tubes) fixtures that run on 277vts. Some 10 of them or more, with nice speckle covers that Id like to put up and replace the single 4' fixtures.
Ive been using a couple 3 tube, 4' fixures that are already 277 volts in odd areas and running them off a 240/120 single phase transformer..hooked up backwards, with no issues, for a number of years.
My "HV" (mains) standard power runs between 240 and 250 volts out in the shop off the breaker panel, but Ive been concerned about isolating the lamps so Ive used old machine tool transformers hooked up backwards.
Ive been checking the "new" 4 tube fixtures out and they all seem to fire up well and Ive got several new cases of 4' T12 bulbs in the racks along with a partial case of T8 4' tubes. Ive stuck in T8s in the older fixtures over the years and they work fine even missmatched with a T12..but I generally replace both.
So at this point in time...Im getting ready to put up the 8' fixtures..but Im concerned about how to power them up.
1. Is it "kosher" to simply hook them to an unused 240 single phase breaker? 2. Is it better to use a transformer and isolate them from the "mains power"?
3 If I should install a transformer...where do I find a 240-277 step UP transformer cheaply? Or several of them (welding shop needs one as well
4. How many watts does each 4' pair actually draw? 90 watts? Each of the 8' fixtures has 2 ballasts, one for each 4' pair.
I tend to work out there at night..and with Pacific Greed and Extortion charging me far more than the national average...my power bills at HOME have been around $400 a month this summer. This with a 1hp swamp cooler motor running 24/7. (which really hurts!!!)
Id like to have lighting in the shop that will work for me..but doesnt break the bank. Work has slowed down tremendously (not had a service call in a week and a half) and its not going to get much better Im afraid...California and the US manufacturing has just declined..yet again.
Id like to find some pull chain lighting switches that I can mount on each 8" fixture to either kill the entire fixture..or just half of it (double ballests) and help keep the lighting costs down as well. Ebay has "pull chain" switches for $4 each..but that will add up fairly quickly if I install 10 lights.
Any suggestions/recommendations on setting up my lighting that will not break the bank?
Thanks
Gunner
-- "Confronting Liberals with the facts of reality is very much akin to clubbing baby seals. It gets boring after a while, but because Liberals are so stupid it is easy work." Steven M. Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Your best bet is to install T8 fixtures over your machines and switch them individually. You can get decent Lithonia fixtures at Home Depot with real ballasts for pretty cheap money, at least here in NY. Payback on using T8 instead of T12 is quick, and task lighting is also a good way to save money. Buy a fixture at a time as you can afford it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 9 Sep 2012 10:19:19 -0400, "ATP"

But which voltage?
Gunner
-- "Confronting Liberals with the facts of reality is very much akin to clubbing baby seals. It gets boring after a while, but because Liberals are so stupid it is easy work." Steven M. Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I would just buy new 120v fixtures. I actually have some nice indirect 277 T5 fixtures that I wanted to use but eventually decided installing a buck boost transformer and having a different voltage in the shop just wasn't worth it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
ATP wrote:

What's the big deal? A single 24 V transformer in boost configuration will drive all the lights. 277V is 115% of 240, and 264 V (240+24) is within 5%. Standard light switches are rated for 277 volts. 80 watt lamp at 277 draws 0.2888 amps. Round that up to .3A per tube for easy calculations. 40 Watt would be about .15A. 55 feet only has room for a little over six eight foot fixtures in a single row, so the maximum load would be .6A * 6 or 3.6A if all six fixtures are on. If he used the other four fixtures over machines, that would be another 2.4A for a total of 6A at 277 Volts. You don't need, or even want isolation on the fixtures. The housings should be grounded, so a fault will blow a fuse, or trip a breaker. They used to put a fuse in some brands of eight foot fixtures, so a failure wouldn't take out all of the light fixtures. Not a bad idea, but the fuses need to be rated for 600V circuits to prevent a plasma arc inside the fuse.
You can even wire the fixtures to turn on pairs of tubes instead of all four, with some ballasts.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 09 Sep 2012 14:16:32 -0400, "Michael A. Terrell"

So let me get this straight..Im very weak here...
input side is 240vts. Output side is 24 or 32vts..simple step down transformer, right?
Hook one side of the 240 volts to one 240 term..and wire a jumper around to the low voltage side and connect to (1) 24 volt term
The othe 240 hot goes to the other 240 input term..
The remaining 24 volt OUTPUT terminal then becomes 264 volts output along with the jumpered 240+24 volt tern?
Do I have that correct?
And if so...where do you recommend I put the fuse(s), on both sides of the transformer..single input and single output terminals?
Im VERY weak on transformer work. Shrug. The stroke took a lot of what I did know..away, from the looks of it.
I may..may have (3) decent sized "buckboost" transformers on a board out on top of one of the racks. Used for bucking UP machine tool voltages as I recall. Ill have to climb up and check. They were as I recall..used on a 3 phase machine..hence 3 of them.
Gunner
-- "Confronting Liberals with the facts of reality is very much akin to clubbing baby seals. It gets boring after a while, but because Liberals are so stupid it is easy work." Steven M. Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gunner wrote:

Yes. Like a control or rectifer transformer used to provide 24 volts vopr a machine.

Yes. She the photo in the link to help you visualize it. You can think of it as a Variac set in boost mode, if that helps.

http://acmefaq.files.wordpress.com/2012/05/buckboost3.jpg sows how to connect a transformer in boost configuration. The 'H' windings are the 240 side. The 'X' windings are the low voltage secondary. If they are connected in phase, they raise the output voltage. If you reverse the phase, it will subtract from the line voltage. Both sides show split windings, so just ignore the H2 to H3 and the X2 to X3 connections if your transformer has single windings. I would put a 10 to 15 Amp fuse or breaker after the transformer, and use a 15A circuit breaker in the panel.
Feel free to email me if you have any other questions.

I would mount one in a box, if the terminals are exposed. If they have a wiring compartment, just mount it next to the breaker box & wire it in. This is like that repair I did last year to that Ineco pipe bender that was reporting low voltage. BTW, they lost a second computer in that thing. Luckily, I was able to repair the oldest one so they didn't have to wait for a replacement from Italy. I'll try to post photos of the second controller before & after I repair it. They will be posted on my Fliker account, until I start a repair blog. http://www.flickr.com/photos/materrell /
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Yup. You will have either 264 or 216. If 216, reverse the connections on the 24 volt transformer secondary

Correct. The secondary of the 24 volt trans just needs to be able to handle the full load current.

Fuse the load and the transformer secondary (which are in series) or simply fuse the parallel combination of the load and the transformer primary. If you think you need to fuse anything beyond the panel protection (fuse or breaker)

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 09 Sep 2012 14:16:32 -0400, "Michael A. Terrell"

I just went out and pulled down the (3) transformers on a board (G) that were hooked up for buckboost. They are Acme 1kvas and I just downloaded the data sheet from Acme. Shows exactly how to do it..and I was right in my last post.
Thank you!! A life saver!!!
Ill put a fuse on the single input hot leg (H1X4) and one on the single output leg. ( That will unfortunately leave me the H4 hot ...hummm..no..if I put it on the input side of the H4 pass through...and another on the X1 output..thats three...hummm unless I have some doubled breakers..that will cover the input and output side with two (double) breakers. Or do you think I need to put fuses on the output side and just a double breaker on the two input lines?
What would YOU do?
According to the data..this thing in buckboost will handle 41 amps and Im not going to have more than about 15 amps worst case sceanario with every light in the shop on at the same time.
My apologies..but I appear to have just discovered another hole in my memory left over from the stroke. I know Ive done these before..quite a few of them. In fact..the 3 phase buckboost I originally installed some 10 or so years ago to get a machine up to voltage...as I recall..they had about 190 volts in the shop..and the VFD was kicking out with an undervoltage alarm..so I put this together and ran their lathe until they redid the entire shop and service..and I got to "scrap" it. <VBG>
And now Im relearning how to do it!! Yippeee!...sigh. Gunner
-- "Confronting Liberals with the facts of reality is very much akin to clubbing baby seals. It gets boring after a while, but because Liberals are so stupid it is easy work." Steven M. Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Gunner wrote:

I would just use a 15 or 20 A double pole breaker on the prrimary, and a 15 A 600 V rated fuse in the 264V output from the transformer. If a fixture shorts, you'll lose the fuse. If the transformer fails or the wiring is damaged, the breaker will trip. It will also remove all power from the fixtures when you need to replace a ballast or socket.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I wouldn't screw around with any fuses in the Buck-Boost transformer at all - just feed it from a 2-pole 240V 20A breaker if you're using all 12-gauge wiring, 15A breaker if some is 14 or16-ga cords.
If you want to save yourself some heartache, get panel-mount fuseholders and 3A or 5A fast-blow fuses, put one on the side of each fixture connected to the Hot lead to each ballast.
With a dozen fixtures in a Carport mounted at 8' - 9' it's not a huge problem to track down a shorted ballast...
BUT it's a good habit to fuse 277V lights, because when you can put 30 to 50 High-Bay fixtures on the same 277V leg in a Warehouse, tracking down a single shorted fixture will take you all day (or more) and drive you nuts as they yell "What's taking you so long? We can't work with the lights off!"
Whereas the one fixture with the burned ballast will pop it's fuse and isolate itself - You find that fuse blown, check the ballast before you replace the fuse.
--<< Bruce >>--
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 09 Sep 2012 23:48:55 -0700, "Bruce L. Bergman (munged human

Excellent suggestion!! I have a coffee can filled with new fuse holders . Much obliged!!
Gunner
-- "Confronting Liberals with the facts of reality is very much akin to clubbing baby seals. It gets boring after a while, but because Liberals are so stupid it is easy work." Steven M. Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 9 Sep 2012 13:35:07 -0400, "ATP"

Buying...is out of the cards at the moment. I might be able to start swapping ballasts over time...but...there is no money for changing fixtures. Seriously.
As long as I dont have to spend money..Im golden.
Gunner
-- "Confronting Liberals with the facts of reality is very much akin to clubbing baby seals. It gets boring after a while, but because Liberals are so stupid it is easy work." Steven M. Barry
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I've gotten panic phone calls from Kinkos locations: "They sent me a 277V Poster Laminator and the building only has 240V - HELP!" If you really want to use up those fixtures till they die, go find yourself a 120/240V to 16V/32V "Buck-Boost" rated transformer.
They are NOT all suitable for Buck-Boost Autotransformer use - Read The (Friendly) Manual, or the nameplate for mentions that it's suitable, or get the make and model and pull up the cut-sheet before you try it.
Some craptastic Lighting and Signal transformers use thin insulation on the secondary that will break down seeing 277V to ground instead of the 32V expected. Rule #1 - Magic Smoke Escape is bad.
Give it 240V in (always use a Handle-Tie 2-pole breaker!) and wire it by the instructions for Boost, and you get 240+32= 272V Single Phase. 5V low = Close enough for Government Work.
A 1KW rated transformer will Boost like 3KW to 4KW of load - read the instructions. The transformer "load" is all used to kick the output voltage higher, and it's only a percentage of the total output. Again, Read The (Friendly) Manual, it tells you how to calculate it.
And when you get new fixtures or replacement ballasts, get 120V.
Some of the fixtures are coming stock with Universal ballasts that take whatever you feed them, be it 120 - 208 - 240 - 277V - Some even take Japan's 100V 50Hz.
--<< Bruce >>--
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

So these fittings are intended for 277V (star) operation off a 480V (delta) three phase supply.

Many ballasts are dual rated 208/277V, so correct operation off 240V is not surprising.

As the fittings are rated for use with a 480V three phase supply, your concerns are almost certainly unjustified.

Yes - but only if they are dual rated.

Two questions, but lets leave isolation aside. You need a boost transformer to 277V (nominal) if the ballsts are not dual rated.

Any transformer with a 240V primary and a 30-40V secondary can be wired as a boost autotransformer. However this DOES NOT PROVIDE ISOLATION Asuming a 35V secondary, the primary only carries 15% of the lamp curent. If the secondary current rating is sufficient, its good, Dont worry about the VA rating. An autotransformer will be much smaller/cheaper than any other solution.
N.B. it would be preferable to use a pair of 18V transformers to boost each side of the supply equally to keep the 277V output centered on neutral. This is quite possibly not to code, so wire a suitable wall mount male connector to the lights and build the transformer in a 'portable' housing with flex leads.

Data should be on the ballast. Add them up. If in doubt, MEASURE!

HTH Ian.
--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
My shop is full lighted with standard 8 foot fixtures. In really cold mornings they are slow to come to full power also.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

I used to just brush them with a corn broom to get them to "fire"
--
Gerry :-)}
London,Canada
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@rogers.com wrote:

Sure, but that only works in Canada!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 09 Sep 2012 18:44:36 -0400, "Michael A. Terrell"

5W+ VHF or UHF two-way handheld radio, preferably on an unused frequency. Stick the antenna between the bulbs, and sweep back and forth while keyed, saying "AAAAAuudio!" - Bing! External Starter.
Still means you've got a lamp with a bad filament, or a weak ballast that isn't putting out start pulses, or it's way cold below the rated Start temperature. The first two need fixing.
--<< Bruce >>--
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
"Bruce L. Bergman (munged human readable)" wrote:

Or the fixture isn't grounded. I ran into a new fixture that was installed on old knob & tube wiring that was erratic. Touch the fixture and it would light. I put a .01F 2KV ceramic disk capacitor between neutral & the floating fixture to cure it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.