Light bulbs keep blowing

A voltage fluctuation is one thing, and if the voltage fluctuates with the load, it is likely related to bonding of the neutral. Spikes are another thing, and most of them are generated by your own equipment starting, stopping, and changing speed. Everybody here probably has a favorite way, or an opinion on dealing with spikes, and possibly sags. I say start with the simplest solution. I have had excellent results using some rather primitive, yet robust equipment manufactured by "Delta Surge Arrestors".

These guys make surge and lightening arrestors and a bunch of other stuff. Very cheap, very effective, and robust. A good place to start, and to leave in place in conjunction with the more elegant things you might try if these don't cure the problem. I have cured a couple of friend's AC drive problems with some 35.00 parts from these folks. Drives that used to burn out major components up to twice a year are now into their third year without a problem. For a sophisticated "point-of-use" filter, try something that incorporates a combo of gas discharge tubes, chokes, and MOV protection. That about covers the spectrum for high, medium and low level spike shunting. A high quality unit will have all three. It's been a while since I touched on this, so I have no direction for you on that.

try a test. use a device like a Sola power conditioner

a bank of lights. put all new bulbs in for the test. put all new bulbs in another zone as a control. see which zone has more problems.

some sort of ballast is usually a part of a florescent light fixture.

it is possible that whoever is buying supplies is simply buying the rock bottom cheapest lamp possible then scratching his head wondering why they don't last very long. at one of my facilities the new high efficiency fluorescents don't seem to last long. even the new electronic ballasts fail with annoying regularity.

I assume that you mean fluorescent tubes and ballasts?

AFAIK, these things are pretty much unaffected by poor quality supplies

- by their very nature they stabilise the voltage across the tube itself. Only if the voltage is dropping low enough to cause the lamp to go out should this affect lamp life, due to increased restarting (IIUC, one start reduces lamp life by about 15 minutes).

Buy better quality tubes, perhaps?

I noticed from their website they make arrestors for 762 volt service "for 762 Volt Oilfield Applications" I never heard of such service. A while back there was a topic for different types of services available. Here's another one.

It makes sense, sort of, if the 762V is phase-phase, the phase-neutral voltage would be 440 volts. You could use 440 volt delta connected motors or other devices if rewired in a wye configuration.

Not sure why it's not shown as 831 volts (phase-neutral 480V).

On Thu, 11 Jan 2007 07:49:13 +0000, no Gave us:

I don't see a reason for this to be true, but I suppose it is possible.

We have IR office and even hallway lights that rarely get switched on or off by actual hands. They cycle all the time. Perhaps bulb brand is the culprit.

a new outdoor sign illuminated with 4' fluorescents. the bulbs were not lasting 30 days. a photo controller had been installed an it turned out that passing car and truck headlight at night were turning the sign off and on.... not enough delay i guess. running the lights 7-24 fixed the problem.

web research turns up a variety of articles.

On Thu, 11 Jan 2007 21:42:59 +0000 (UTC) Michael Moroney wrote: | "Long Ranger" writes: | |>simplest solution. I have had excellent results using some rather primitive, |>yet robust equipment manufactured by "Delta Surge Arrestors". |>

These guys make surge and lightening arrestors and |>a bunch of other stuff. Very cheap, very effective, and robust. | | I noticed from their website they make arrestors for 762 volt service | "for 762 Volt Oilfield Applications" I never heard of such service. | A while back there was a topic for different types of services available. | Here's another one. | | It makes sense, sort of, if the 762V is phase-phase, the phase-neutral | voltage would be 440 volts. You could use 440 volt delta connected | motors or other devices if rewired in a wye configuration. | | Not sure why it's not shown as 831 volts (phase-neutral 480V).

Probably for traditional reasons like you see a lot of stuff listed as

440 volts or 460 volts instead of 480 volts.

| MassiveProng wrote: |> On Thu, 11 Jan 2007 07:49:13 +0000, no Gave us: |>

|>> (IIUC, |>> one start reduces lamp life by about 15 minutes). |>

|> I don't see a reason for this to be true, but I suppose it is |> possible. | | a new outdoor sign illuminated with 4' fluorescents. the bulbs were not | lasting 30 days. a photo controller had been installed an it turned out that | passing car and truck headlight at night were turning the sign off and | on.... not enough delay i guess. running the lights 7-24 fixed the problem.

Point photo sensor straight up from a height with a cone shield.

Or just use a timer and an almanac.

Or, really go all out and buy an astronomic timer.