Is a ballast required, or merely acceptable, for this Philips InstantFit LED tube?

Question

Rather than replace a dead ballast in a fluorescent fixture, I've decided to simply bypass and move to LEDs. However, I think I may have grabbed the wrong kind of replacement tubes the other day in Home Depot. They are in the Philips "InstantFit" range, and are specifically intended to be used without having to remove the ballast. But my question is the following. Is it merely that you don't have to remove the ballast (i.e. but you can if you want)? Ot is it the case that you must not remove the ballast?†

I ask because all the instructions I've been able to find are a tiny bit ambiguous (to me). In the "Warnings and Safety" section on page two of the data sheet it says††:

Philips LED T8 InstantFit lamps will only operate properly on compatible instant-start ballasts.

However, there are two ways to read that. One, which I now think is the intent, is:

Philips LED T8 InstantFit lamps will operate properly only if used with a ballast, and it must be of a compatible, instant-start type.

But the other is:

Philips LED T8 InstantFit lamps will operate properly with or without a ballast. However, if a ballast is used, then it must be of a compatible, instant-start type.

Anyone know definitively which it is?

Various numbers (from the box):

• Model: 9290012265
• Ordering Code: 20T12 EM LEF/48-4000 IF G 10/1

thanks.

† If so, that's fine. But then I need to replace them and get the kind intended for ballast bypass, of which there are several.

†† That link is to the "global" version. Curiously, the almost-but-not-quite-identical US version does not make the same explicit point.

Answer 1

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 correct.

The data sheets you link are highly ambiguous. But that's not so weird when you look at the Electrical Code, NEC 110.3b:

NEC 110.3(b) Equipment must be installed and used in accordance with any instructions included in the listing or labeling requirements.

The operative words are instructions and labeling. A data sheet is neither.

So you need to review the labeling on the item, or the instructions in the box.

Be warned: if you find that data sheet inside the box, that is bad. It means this thing is probably counterfeit: the counterfeiters found the same PDF you did because it was the first/easiest document to find.

I am always suspicious of the bargain priced items at the big-box. Even legit brands often "make" items specifically for one big-box store. If you have a part number that only associates with one big-box, run screaming.

Answer 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.

Answer 3

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 InstantFit T8 LED lamps are intended for use in conjunction with a magnetic ballast. Please do not connect the lamp directly to mains voltage 120/220/240/277 VAC.
• Ensure all parts and accessories are in the package, including instruction guide, label, driver and InstantFit T8 lamp
• Modifications to the product void the warranty
• Compatible with T12 rapid start magnetic ballasts
• Please refer to www.philips.com/instantfit for the latest ballast compatibility guide

Answer 4

If the led tube comes with a 'starter' replace the original neon's starter with the one that comes with the led tube and you'll be fine, if no starter is supplied you will almost surely have to rewire the fixture excluding the ballast.

Answer 5

I purchased a Philips instafit LED tube and it didn't work with my old ballast, so rather returning it, I took the whole thing apart.

The LED light was double ended, with a 160C Thermal cutoff at both ends, followed by a solid state noise suppression capacitor, followed by a 160 volt microfarad electrolyte capacitor and then the light strip.

The electrolyte capacitor is the killer for AC functionality. The electrolyte capacitor defeats the use on AC, as the capacitor plates will charge and then discharge 60 times a second due to the alternating current. Thus no juice gets to the light strip.

So it is not a safety issue, but just bad design from Philips that prevent the use of these instafit bulbs without a ballast.

Answer 6

LED stands for light emitting diode, so not an AC device. The light is emitted when forward biased, so a rectifier is needed to avoid high current in the case of reverse bias and then current limiting to provide the correct operating current. Does not need a ballast but might work with one.

Answer 7

I did a ballast bypass for a friend that had a barely working Instantfit T12. It didn't work. The same tube worked fine in a different fixture with ballast.

We bought a different LED bulb and that didn't work with the bypass, either. After a bit of head scratching, we realized that we grabbed direct replacement (ballast required) LED T12 tube by mistake. Once we purchased the bypass tubes, they worked in the bypassed fixture right away.

(We eventually came to the conclusion that the original ballast was marginal and failing, but working enough to partly light the Instantfit.)

Bulbs built explicitly to be direct replacement apparently need the higher output voltage coming from the ballast in order to work. US 120VAC is apparently too low, while perhaps 220 in other markets might work on the Instantfit even without a ballast.