LED not working with new fixture w/ compatible ballast

[Hockyfn30]

I just bought a new 8ft, four bulb florescent fixture to use with the Philips instantfit t8 led bulbs. The fixture included the osram qtp4x32t8/unv isn-sc ballast which as far as I can tell is included on the compatibility list from the philips website.

Now that the fixture is installed, the led bulbs will not light. I put in old fluorescent bulbs just to make sure everything was wired up correctly and those are working fine. Any suggestions of what to check next? I thought I did the right homework verifying they had the right ballast (an important detail from what I could tell reading the reviews of those bulbs) but maybe I'm missing something else.

 

[AP514]

Pic's ??

 

[pepi]

Yeah I got one, buy an LED tube that can be direct wired ......... think about it, a direct wired LED is 50% more efficient .....

Why have two failure points, ballast and tube..? Seems like a no brainier.

Here is a link that tells you what I'm writing about T8 LED Tubes

One more point even when using a ballast and LED compatible tube the fixture will need a wiring modification.

Devil is in the details .....

 

[cybrdyke]

HockeyFn, yes the ballast is compatible.
From a troubleshooting point of view, you know the ballast is good, and you know the sockets are good. That leaves only two things suspect. Either the lamps are toast or the fixture is mis-wired. Yes, I see brand new fixtures mis-wired all the time. The fluorescent tubes can fire even if the fixture is mis-wired, but the LED tubes are less forgiving.
If you care to double check the wiring, you should have 2 lamps with blue leads and two lamps with red leads. On the opposite ends from blue and red, there's two yellow wires. Each yellow wire will be connected to a socket and then jumpered over to a second socket, probably with a white jumper wire. Make sure one yellow is feeding only blue-wire lamps and the other yellow wire is feeding only red-wire lamps. If it's wired correctly, then you can just assume that you have dead lamps.
Good luck,
CD

 

[cybrdyke]

think about it, a direct wired LED is 50% more efficient .....

Direct wired LED tubes are no more efficient than instantfit tubes. In fact, in some cases instantfit tubes are more efficient than direct wired tubes.

Why have two failure points, ballast and tube..? Seems like a no brainier.

There's a lot of reasons to use ballasts, but for the purposes of most Garage Journal members, bypassing makes a lot of sense.
FYI-you still have 2 points of failure when bypassing the ballast. They're both inside the tube. Because the driver is so tiny (to fit inside the tube), it's not very robust. A good ballast will far outlast a tiny LED driver.

One more point even when using a ballast and LED compatible tube the fixture will need a wiring modification.

No wiring modification is necessary. Just swap lamps is all.

 

[Bert_]

Sylvania makes (or at least someone used to make) a really nice retrofit kit. It used an LED tube but rather than put the driver inside the tube you replaced the fluorescent ballast with a provided LED driver. It kept the driver and LED's separate instead of packing it all in the tube. In my opinion that was a much better system and should last longer than the tubes normally used. Unfortunately they were not competitive as far as price goes and didn't seem to catch on.

 

[cybrdyke]

Any suggestions of what to check next? I thought I did the right homework verifying they had the right ballast (an important detail from what I could tell reading the reviews of those bulbs) but maybe I'm missing something else.

Hey Hockyfn,
Try this...
Install the LED tubes into the sockets and then rotate them 180 degrees so that they are facing up, not down. This will reverse the pins in the socket. Let us know if the tubes come on when you do that.

Sylvania makes (or at least someone used to make) a really nice retrofit kit. It used an LED tube but rather than put the driver inside the tube you replaced the fluorescent ballast with a provided LED driver. It kept the driver and LED's separate instead of packing it all in the tube. In my opinion that was a much better system and should last longer than the tubes normally used. Unfortunately they were not competitive as far as price goes and didn't seem to catch on.

Universal Lighting makes a retrofit kit like this. Very versatile and works great.
CD

 

[Dragfluid]

Hey Hockyfn,
Try this...
Install the LED tubes into the sockets and then rotate them 180 degrees so that they are facing up, not down. This will reverse the pins in the socket. Let us know if the tubes come on when you do that.




Universal Lighting makes a retrofit kit like this. Very versatile and works great.
CD

Thanks for that info!

 

[pepi]

Direct wired LED tubes are no more efficient than instantfit tubes. In fact, in some cases instantfit tubes are more efficient than direct wired tubes.

There's a lot of reasons to use ballasts, but for the purposes of most Garage Journal members, bypassing makes a lot of sense.
FYI-you still have 2 points of failure when bypassing the ballast. They're both inside the tube. Because the driver is so tiny (to fit inside the tube), it's not very robust. A good ballast will far outlast a tiny LED driver.

No wiring modification is necessary. Just swap lamps is all.

That's funny, tell me who replaces a dead driver or the LEDs in the tube?

Moving your statement forward, each LED would be considered a point of failure

I cannot believe you lack the common sense to not realize that a sealed unit. Is the signal point of failure. That statement is really weak and illogical, never mind plain wrong for the discussion.

FYI that's nonsense

Greg

 

[cybrdyke]

That's funny, tell me who replaces a dead driver or the LEDs in the tube?

Moving your statement forward, each LED would be considered a point of failure

I cannot believe you lack the common sense to not realize that a sealed unit. Is the signal point of failure. That statement is really weak and illogical, never mind plain wrong for the discussion.

FYI that's nonsense

Greg

Ummm.....I dont think that. I was simply reminding you that there is still 2 components. Dont get all fired up about it.
Geez.
CD