CFLs and power factor?

[BioHazard]

I need more lights in my shop, I want to brightly light about a 2400 sq ft area. Rather than using linear fluorescents I was thinking about using approximately 60 23w compact fluorescent bulbs for a variety of reasons.

Problem: I'm confused about the power factor on CFLs. Apparently it is very low, somewhere around .5. Someone is telling me this will limit the number of CFLs I can have on one 20 amp circuit to about 20 even though the wattage is nowhere near the breaker limit.

It's become a bit of a controversy on another forum. I'm curious what you guys have to say. Does the low power factor in a CFL mean that I can't plug more than about 20 into a 20 amp circuit, even though the total wattage would only be 460? I've never tried to plug in that many CFLs at once but that doesn't seem right to me. Should the circuit breaker and wiring be sized for the wattage of the bulb, or the VA, or something else?

[mike90045]

I know inverters will respond unfavorable to the lame PF in CFL & LED bulbs.   Why not use the T-5 or T-8 fluorescent tubes - better efficiency per watt then CFL's and you can get corrected ballasts.


http://en.wikipedia.org/wiki/Electrical_ballast
http://www.grainger.com/Grainger/GE-LIGHTING-Ballast-5GVC1

[LowGear]

Would one of those Power Factor corrector con jobs help?

These T8 ballasts hooked up with the skinny tubes would work better in cold environments as well - so I'm told.

Casey

[BioHazard]

It's mostly about cost, I can get the same number of lumens out of CFLs @ $3.25 each than I can from T8s which would cost about twice as much after buying fixtures. With the CFLs I don't need "fixtures", any edison socket will do. I understand the linear tubes are a bit more efficient but that isn't much of a concern here. Shop stays at least 50 degrees so temp isn't a concern either.

Would one of those Power Factor corrector con jobs help?

That was one of my first thoughts, but they are like $150.........not sure if that would work or not. Or even is necessary.

I understand they make high power factor CFLs, for high dollars, I just wonder how many you need on a circuit before power factor becomes an inssue?

[mike90045]

The power factor corrector gadgets are made for motors, I don't know if they will work on CFL's.   But you can get corrected CFL's they are mandated in europe, and will be soon in the states too, the wacky PF is affecting the major grid utilities, as folks switch to CFL's.

So in your shop, it depends on how much "overhead" your generator or inverter can manage for the bad PF, as to how much you can run off it.

[Thob]

My problem with the CFLs is that they don't last anything like what they claim.  I don't have any hard numbers to compare, but I pretty sure I get several times the life out of the old fashioned straight tubes.  You may find it's false economy to buy the cheaper CFLs.

[BioHazard]

My problem with the CFLs is that they don't last anything like what they claim.  I don't have any hard numbers to compare, but I pretty sure I get several times the life out of the old fashioned straight tubes.  You may find it's false economy to buy the cheaper CFLs.

I have found the same thing, I've thrown away plenty of dead CFLs long before their time was up. I think the biggest problem for them is heat and lots of on/off cycles, which shouldn't be much of a problem in the shop. They will all be in the open air and not switched on/off very frequently. At about $3 each I can order a few extras for the inevitable.

I originally wanted to do T8s but I just think the CFLs would be easier to hang from my metal ceiling. Tonight I went to a store that sold lamps and noticed all their displays had CFLs in them, I wonder if they were all plugged into the same circuit?

[vdubnut62]

May or may not be relevant, lightning struck a tree in my yard and took out every CFL in the house that was directly in line of sight
of the strike. Got a couple of ground fault outlets, all the phones, modem and the refridgerator too. The LED's lived through it though.
Ron

[DanG]

If you can find a CFL in the wattage & Kelvin temperature you want... AND have it approved for base-up operation. So far 98% of the ones I've looked at have the 'table lamp' graphic use symbol on the packages denoting base down and non-enclosed fixture with plenty of air above it.

CFLs usually depend on smoke stack cooling - the tubes heat generates an updraft that pulls cool air up and over the ballast. If they are anywhere the air can not 'turn-over' as dead air space they will cook - if the bulb is beneath the ballast they will cook - an on and on.

I was hunting shop lights and nabbed a bunch of 27W & 65W Fluorex outdoor security floodlights from 'lights of america' when a retailer was closing shop and found I had to cut cooling ports for the bare ballast PCB to cool if I wanted to get anywhere near the 10,000 hours claimed. Silly expensive toy if you're not paying 20¢ on the dollar for them new but they have good light throw and are almost pleasant to work under.

With the T-8 install in my kitchen I found I could buy magnetic ballast fixtures and re-ballast them with electronic style for ~25% less than purchasing the E-ballast identical model but the stars must've been aligned just right that week

http://sound.westhost.com/articles/il-cfl-3.htm linked from
http://sound.westhost.com/articles/incandescent.htm#pf

Also found while surfing was this little factoid: "Sandia National Labs runs reactive load tests on inverters.. . . ..Trace SW5548 inverters powering loads with a 1.0 power factor run 4 percent more efficiently than a 1,000 watt load with a 0.5 power factor. That means more amps out of the battery. At 3,000 watts, the efficiency difference is 7 percent."

[mike90045]

May or may not be relevant, lightning struck a tree in my yard and took out every CFL in the house that was directly in line of sight  ....

Did being turned on or off have any difference ? 

Are you on grid, or off grid

Any household surge protection like Midnight SPD's or Deltas ?

[SteveU.]

Good post DanG.
Like most here I have too chased CFL's through three generations of improvements. Quicker turn on now. Better light quantify and quality. Better fixture sizing. But Life v. Cost v. True cost of operation v. Disposal has been a continuous bogus hype nonsense.
Took me years and far too many bulbs to figure out the positional/heat factor. Upright non-enclosed mounting DOes get close to their  claims. Sideways non-enclosed mounting halves the life. And mounted downward, enclosed or non-enclosed, kills them quicker that a standard Edison incandescents.
Packaging now hints at this. But NO mention in the Public Power suppliers written or televised hype push us all into to all CFL's.
I do not think anything ever going to beat the physics of this heat. Look at your own fixtures. I Want my porch lights and kitchen can lights and Shop lights to illuminate DOWN. Not wastefully UP.
So fella's this is one more area of my life that I have to turn bootlegger attitude. Stock up on soon to be "illegals" and support a black market bootlegged in from the 3rd world to assert common sense and freedom of choice.

One more time an example of "Make haste s-l-o-o-o-l-y!" in all things social and technical involving a BIG "Everybody must" brush.

If Life was your #1 critieria then go with a 12 volt incandescent marine/RV bulb system. All I have used now for years as my rough service underhood repair illumination. Bulbs last for YEARS being banged around around and dropped.

All my own opinions
Steve Unruh

[BioHazard]

These are the CFLs I was thinking about using:
http://www.1000bulbs.com/product/1587/FC23-FEIIS23W50.html

With a 15 month warranty I can send 'em back if more than a few go bad early. Doesn't say anything about "base up" operation but they would be in completely open porcelain sockets.

I do have a 15w CFL in my garage that has been burning 24/7 since sometime in the year 2000. Still works. That's almost 100,000 hours....

[DanG]

Write the company and ask about the ballast/power factor and the recommended burn positions on that one -

And ask if they have a better alternative, telling them the particulars of quantity and circuit capacity available. 

[BioHazard]

Has anybody ever heard of EnergyMiser bulbs or the company that makes them? Google only shows me results from 1000bulbs.com....

[Thob]

Back to the original question about power factor - do you own a kill-a-watt?  I still have one on my "must buy" list.  They can measure power factor, and a little first hand experimentation might be very helpful.  You know, actually measure a sample of the actual bulbs you want to use?  Real data is worth more than a room full guesses.