Electronics → T8 retrofit ballast

So its a 2 tube t12 and I picked up a 2 tube ballast however I noticed on the old ballast it has two yellow wires and two blue and two red.. my question is on the new ballast it has just the blue and the red I assume the tombstones need to be changed out to the shunted version?

Yep

wiring diagram on ballast will tell you how to wire them

Yeah but I was going to buy shunted tombstones however they don't have them at hd so I'm just going to wire them

I would recommend against replacing the tombstones unless there are other reasons to do so (such as cracks in the casing or badly worn contacts). Keeping the regular tombstones allows the use of instant start T8 (simply connect both wires from the same tombstone together) as well as program controlled rapid start T8 (which do require the separate connections to utilize the heating element).

It is too late now since you apparently already bought the new ballast but for maximum bulb lifetime you should use PCRS ballast and bulbs when switching from T12 to T8. You won't find those at the big box stores since they make more money of you from frequently replacing your IS bulbs.

I know why you are saying using that type of ballast but we had instant starts in about 120 fixtures and they were switched.. in 7 years I think only 5 or so I had to change.

I think the rapid wear on the bulb is a little overblown

My replacement electronic ballast was the same. No need to purchase new tombstones, just connect the tombstone wires to create a shunt.

It is good practice to double check the shunted connection, because if only one side is connected everything will work but bulb life will be reduced.

/tom

Well it's all good but the stupid lens cracked.. the fixture looks like from the early 90's a mercury brand..

It's 4' by 11" and thinking a 2 tube fixture cover would work... nope!

Why was this moved to electronics?

Prolly so we could beat you with wet noodles too..

Here just get rid of the whole ballast.. »www.birddogdistributing. ··· -Lights/

Lol too expensive when you have a whole bunch to change

I'm changing to them fixture by fixture. After I found out 1 of those bulbs puts out more light than 2 4' t-12 florescent, the power draw went from 55W to 15W per fixture, and most importantly it comes on every time I flip the switch, I was sold! The last item being the most important to me, as I was getting extremely annoyed at the florescent lights not starting whenever they didn't feel like it.

You may be interested to know that Home Depot is selling Philips LED tube lamps which are designed to work with T8 instant start ballasts. Should be less than $15 each on sale.

today's regular price: $237.22 for 10 pack
»www.homedepot.com/p/Phil ··· Z1z132on

That's interesting to see.. wonder why they haven't made those available in stores yet. Those are showing about 200 lumens less output. The one thing they didn't consider (or at least mention) is the loss that will still be present in the ballast. Also that you will apparently still need to replace the ballast should it fail.

Where I get mine they now have a "economy" bulb that is 19.99, it has 96 LEDS in place of 300, but the same lumen and power spec.

that's good and all but I would still be in for replacing about 150 rapid start magnetic ballasts... Yes that many of them around here.

These would be good for the truss fixtures but again those are magnetic.. and the side lights between all of those going it sounds like I'm in a substation LOL

I haven't seen them in my Home Depot and I just came back from the store today to pick up 12 Cree BR30's in 65W I have only 17 more to buy.. I could of picked them all up at once but then you are talking about $329 or so.. then I'm going to have to rent the gennie lift as you know the days are starting to get shorter

Question about that site you listed.. how would the light output be from about 20 Ft up? And because the the trusses they have no covers so how do they look when they are on?

I don't know how they are wired.. it's 3 tubes to a truss but how is the ballast wired for that?

My light fixtures have no covers, but are only 10' up. With my light meter I measured more light from a single LED tube than from 2 florescents. As far as looks you don't really notice a difference, unless you are specifically looking at the light.

I'm not sure how 3 bulb ballasts are wired, it's been a long time since I was in one. With the LED lamps I'm using, you remove the ballast and wire both sides of one end hot, and both sides of the other end neutral. Also I put a label under the bulb on the reflector stating "Wired for LED only".

PS excuse the disaster area below the lights called "my shop"

Also I had to take that picture tonight since I just received 6 more LED bulbs, and the fixture to the right will likely be converted by morning.

What do you think is the best way to go as far as converting? I have the truss lights plus lights on the side that face a brick wall.. only 1 or 2 bulbs are out on the lights that face the brick.. all in all for that area alone I'm looking at close to like 50 replacements.. those are the highest to get to.. the others that run along the wall are within arm's reach. I'm just trying to make good use of the lift when I rent it

»www.amazon.com/4-Pack-Hy ··· &sr=1-13

No 347v lighting, is there?

what?

Some lighting circuits in commercial/institutional settings are 347v.
»www.ihsa.ca/pdfs/safety_ ··· uits.pdf

looks like it is more of a Canadian thing.

In the US the other common voltage used for industrial lighting is 277V. That is one leg of a 277/480V 3-phase Y.

/tom

nothing here is 277V for lighting.

I took some pictures of the fixtures.. the stuff on ground level is really old but seems to be single per fixture.. the truss stuff seems to be 2 double and 1 single fixture.

You need to decide on the 3 tube fixtures how much light you want from them. I would think 2 LED tubes will give you the same amount of light as 3 florecent tubes, perhaps more. I think it would likely be more economical to replace all the lights you need to rent a lift for. One lift rental and you shouldn't need to replace again.

Then you can use the good bulbs from up high for the low lights until you convert them.

Ok just ordered these here as they come in packs of 10.. so I'm going to need two more

»www.amazon.com/gp/produc ··· fresh_T1

Hah well I just ordered a pack of 10 from the Hyperikon they happen to pop up in stock again I got the frosted (did not really matter to me) I still need to get 2 more to make up 30...

Now that's just the truss lights and not including the side lights about 20 ft up.. I would guess it's around 20-30 in that area too :-/

makes me wondering during the fixture install did they really factor in bulb changes?

Wow here now and it's a total of 36 tubes for the truss fixture and 34 facing the brick wall and 16 for the fixture at ground level

They shipped and it's only like 3 lbs or so lol

Arrrg!!! Be careful, I was just doing some more conversions, and I had bought 2 different type bulbs. Luckily I noticed the difference before I energized anything but for some silly reason they changed the way these are wired. The new wiring scheme I think is quite stupid! The old scheme was hot to one end either or both pins, and neutral to the other end either or both pins..

The new version is hot & neutral to each pin on one end, with the far two pins apparently shorted with no connection. The wiring diagram allows for the neutral to pass through the non active end to come back to the "live" end. That is to accommodate existing wiring. But what this means is that now I have mixed tubes that can NOT be interchanged and I have to label every fixture exactly how it's wired. In the case of the single end sockets I have to indicate which end is active.

Putting one of the single ended tubes into a fixture wired for dual ended should just come up with a non lit tube. But if you were to put a dual ended tube in a fixture wired for single ended tube... BOOM!

Also aggravates me since I ordered different temp lights and was going to move them around depending on what I liked.. well that's out unless I want to rewire each time..

Yep I saw how some are single end power and that's what I have now