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6

It won't work right. It will overdrive the tube (or underdrive the tube) and you'd get short tube life. It may flicker horribly. It may not be able to strike. Basically the same things that will happen if you put T12 tubes in a T8-ballasted fixture. It's basically a dumb thing to do. If you got a wrong thing, take it back and get the right thing. ...


4

It's the ballast When old magnetic ballasts go bad, that's one of the things they do. I swear, I'm about ready to stick a logbook inside every fixture because I think most of our bulb replacements are in the same 5 fixtures. Decide which type of bulb you want going forward (T12 vs T8) then buy an appropriate electronic ballast. If you want to play ...


4

T5 lamps are usually 54W while T8 lamps are 32W. The ballast's job is to establish the arc then keep the lamp running at the proper level. T5 lamps are shorter so the initial arc may not work well with a t8 lamp, but the problem will be the T5 ballast will allow too much current to flow and drastically shorten the lamp life, possibly causing the lamp to ...


3

Interesting thing about being human is the brain is wired to see what it expects to see. It's hard to turn that off, even if you're a ship spotter or pilot. There is such a thing as LED bars which work both ways, either with a ballast or direct-wire. But they're a lot bolder about claiming so! The ruling word is "only" and your first interpretation is ...


3

The stock sizes of 4' bulb are F40T12 and F32T8. T8s are relatively new. Both make about the same light, the T8 is more efficient. So when they talk about F40, without any further commentary, and particulary when the unit is older, they mean F40T12.


3

You identify the tube type, then the ballast. The fixture decides the tube The fixture and its lampholders are going to decide the size of tube you can use. Within that, you may have some flexibility. Start by looking at the fixture. Look at the length and shape of tube, and the lampholder sockets. Often, it's totally obvious, like the ubiquitous 48" ...


3

1. With HPS, no for smaller bulbs on bigger ballasts. Discharge lights are current devices. They are non-linear (behave almost like a dead short) and so, must be externally current-limited. That's the whole point of a ballast or driver. HPS bulbs work at a specific current in one of four working voltage ranges (page 9): 52V, 55V, 100V or 250V plus or ...


3

You will need to bypass the ballast! Failing to do so will fry the LED. Corncob LEDs are always a bad idea. They are inefficient. They intentionally defeat the best characteristic of LED -- that they make a wedge of light, which is what you really want. Look around at lights. You have wallpack lights painting a super bright spot on the wall (useless), ...


2

The spec sheet specifies Plug and play. That means you do not replace the ballast. The opposite is "direct wire", which is where you do. If it were a direct-wire unit, it would specify which pins to wire to. The spec sheet also explains why it failed initially, in the upper right it says "Feit Electric". You can tell from the errors on the data sheet ...


2

First, that fixture looks permanently hardwired. If so, you'll want to add a ballast disconnect. Code requires it, unless you argue that the fixture is now ballastless. But it's so darn convenient that I add them immediately upon starting work, and then, turn the power back on! Cutting the wires off at the ballast is someting I only do to ballasts which ...


2

After scratching my head - I decided to pull the tombstones out and inspect the wiring to make sure there was no sneaky connections and also nothing out of the ordinary. The older ballasts (original diagram are Magnetic Ballasts with PCB) the new ballast are electronic. I contacted the manufacturer and they suggested to verify my grounds for the ballast ...


2

Ballast replacement is fairly straightforward. I still prefer fluorescent tubes because I can easily find quality fluorescent tubes in 90+ CRI (in fact Menards stocks them), and I have serious doubts about the real quality and longevity of the LED "cheapie" tubes. Start with a "ballast disconnect" For this you need to shut off the circuit breaker ...


2

The given phototherapy tube is a glow start tube with filaments. The glow starter is built into the base. Glow start tubes are usually driven with conventional magnetic ballasts. There might be also electronic ballasts for 2 pin tubes with built in glow starters, but usually electronic ballasts need access to all 4 pins of the tube. The given listing for "...


2

I can confirm Phillips InstantFit work with ONLY specific ballasts and do not work without ballasts. I tried with Utilitech lights and with ballast removed to no avail. I'm done with fluorescent anyhow. They don't work very well in my garage for Michigan winters and don't last very long. I'll get LEDs that don't need ballasts.


2

This is what happens when you walk into Home Depot and buy a bunch of random parts. Which is why I do not like Home Depot. That, and their prices are outrageous. Currently, you have a genuine fluorescent fixture, with a rapid-start ballast. (Or possibly the even better programmed-start type). Hence, the 2 wires to each end of each tube. The 2 ...


2

Fluorescent tubes have 2 pins because each end isn't just an electrode, it's also a preheating filament. This helps the arc to initially strike, with less wear-and-tear on the tube (longer tube life). You have chosen rapid-start ballasts, which start the tube after a very short delay, which is used to stretch bulb life. The other options on the menu are ...


1

The "PS" in your lamp part number means "Pulse Start", which is the way in which the Metal Halide bulb is initially excited to begin putting out light. That means it most certainly has a ballast in the fixture. So to use your LED replacement, someone will need to remove the ballast and run the wires directly to your mogul base socket (you can leave the old ...


1

You don't, unless the ballast label or data sheet says you can. In your case the ballast label says "For 1-lamp operation, individually insulate the yellow leads for 600V" - that is canonical. Further, it makes sense. They need to be capped off from each other because there is preheat voltage on them. Since you need 4 wires and there are 4 wires ...


1

Do not use plug-n-play LEDs - they depend on a functioning ballast and your ballast is suspect. Because then, you'd be at a crossroads. Return the plug-n-play and remove the ballast and get a direct-wire/ballast-bypass LED... Or replace the ballast and stay with PnP and support that ballast forever, even though LEDs don't actually need it. Obviously the ...


1

If it's not on the label, that ballast doesn't support it! Your tube is an F54T5/HO. This is one of the most popular types of tube. It means 54 nominal watts T5 tube type (5/8 inch diameter) HO is High Output length is implied, you just have to know it's 1163 mm. Ballasts support only certain specific tubes, in specific quantities. The popular ones ...


1

In lighting, The letter "T" represents the shape of the bulb, which is tubular. The number represents the diameter of the bulb in eighths of an inch. I/E: A T5 is a tubular bulb that is 5/8" diameter. Lengths of these different bulbs (T5, T6, T8, T9, T10, T12) can vary because the wider the bulb, the longer the bulb can be manufactured. There are also some "...


1

This is extremely common behavior for old fluorescent ballasts, though the reason for it depends on exactly what type of ballast it is. If it is a really old model that uses a replaceable "starter" cartridge, it is likely that the starter needs to be replaced. If your ballast does not require a starter, the issue most likely the lack of a ground plate ...


1

No t5 bulbs are 54w or t5ho are, T8 have a lower wattage 32w for example. The lamp may start but the ballast life and the lamp will be greatly reduced if it strikes (starts). Ballast are designed to limit the current to the lamp. They strike or ignight the gas in the tube , once the lamp starts the resistance starts dropping, the ballast limits the current ...


1

First I check for obvious fitment of the tubes and conditions of the tombstones. For instance one easy problem is failing to rotate the tube a full 90 degrees, so it doesn't properly engage. On T8/T12 tubes there are score marks to help tell you where center is. Can't speak to T5. If that all checks out, and fitting new lamps doesn't make them all ...


1

I buy most of my ballasts on ebay for a couple of bucks, they are new pulls (seller bought new fixtures and immediately converted to LED). I combine them with the newest 90+ CRI tubes ($2 each) and the light is amazing! Don't look at the fixtures, look at the stuff the fixture is lighting up. ALL fixtures can take electronic ballasts, I have converted ...


1

You have a real fluorescent fixture of stout construction. This is a good thing. You can do anything with this, convert to LED, convert to T8 or keep T12. The fixture has two ballasts, you showed a picture of one. It is an old magnetic ballast, which may flicker and run poorly in cold weather. One ballast powers the inside tubes, the other ballast ...


1

Fluorescents are arc-discharge lights, meaning like neon where a high voltage runs the length of the tube, and that arc must be initially struck on startup. 2-pin simply means the lamp does not have electrode preheaters for gentle startup. They are built extra tough to handle this. So a 2-pin ballast needs a somewhat higher startup voltage. That is not ...


1

Not a problem if 1 or 2 fixtures , there 2 kinds of ballast bypass lamps single end or double end first we need to know the type, I prefer double ended because then all existing tomb stones can be used. First if this is a double ended lamp I would tie the center. Or middle tombstones to the hot or neutral it doesn't matter then the outside one at each end to ...


1

The Installation Guide contains important information and notes regarding the installation and operation of the InstantFit T8 lamps. Please note the important points below: Philips InstantFit T8 LED lamps are suitable to replace T12 fluorescent lamps Philips InstantFit T8 LED lamps require non-shunted G13 (medium bi-pin) lamp holders (tombstones) Philips ...


1

I'm a bit alarmed when I hear you say "capped off my yellow wires". A few ballasts do give that instruction, but not for 2-bulb use. I fear you might be matching up wire colors and not following the schematic on the ballast. Thing is, if the old ballast was instant-start, that will totally backfire. As you can see in these typical schematics, red and ...


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