Hi,
Just went through and updated the lighting in my 24 x30 shop. It had six 8' dual tube T12 fixtures I put in almost 40 years ago, most were dying or dead. I wanted to go with LED's and tried to emulate the lighting of an LED re-lamped SevenElevn which had suburb lighting. I managed to ID the troffers used in the SevenEleven but at around $400 each it just didn't pencil out, even for bragging rights. Even tried to make my own with some Cree emitters, the prototype had the light I needed but the cost was still too expensive.
I ended up modifying my existing two tube T12 fixtures to take four T8 tubes. Just finished up two days ago, the light is as good as the SevenEleven, better CRI than my LED prototype, and double what I had with the T12's. The key with the T8's is to get the correct tubes and ballasts.
I used a 500K broad spectrum 900 series phosphor tube with a high lumen output from Litetronics and a matching GE UltraMaxH ballast with a ballast factor of 1.18. The ballast factor is important parameter to look for and determines the tube's drive current and light output. A lot of ballasts are sold as energy savers and have low ballast factors (like .87) they only drive the bulb at 87% of its rating, yes it saves energy but at the cost of light output. My GE UltraMaxH drives the tubes at 118% for more light. I am getting about 1000 LUX at 36" off the floor total power is 909W and if I want to save energy I turn several off. The 900 series phosphor is a nice broad spectrum brilliant white with a CRI of 90. I ended up with 24 T8 tubes arranged in three strings parallel to the 24' wall, one in the center, two midway to the wall on each side of center. The total cost for the bulbs, new ballasts and new sockets with shipping was around $300. This was less than one LED fixture. Glad I did the T8 and not the LED's, light is great, instant on, on hum or flickering, very happy with the results.
Got everyting at 1000bulbs.com
Tubes: Litetronics L-359 F32T8CB50
Ballast: GE UltraMax H part number 71723 (drives 4 lamps)
Sockets: Leviton 23351
Home center stuff is not your best choice for the best light output. Go for premium tubes and ballasts. One post I found suggested you buy cheep low cost fixtures without tubes. Then just toss the ballast and replace it with something really good.
Craig
Just went through and updated the lighting in my 24 x30 shop. It had six 8' dual tube T12 fixtures I put in almost 40 years ago, most were dying or dead. I wanted to go with LED's and tried to emulate the lighting of an LED re-lamped SevenElevn which had suburb lighting. I managed to ID the troffers used in the SevenEleven but at around $400 each it just didn't pencil out, even for bragging rights. Even tried to make my own with some Cree emitters, the prototype had the light I needed but the cost was still too expensive.
I ended up modifying my existing two tube T12 fixtures to take four T8 tubes. Just finished up two days ago, the light is as good as the SevenEleven, better CRI than my LED prototype, and double what I had with the T12's. The key with the T8's is to get the correct tubes and ballasts.
I used a 500K broad spectrum 900 series phosphor tube with a high lumen output from Litetronics and a matching GE UltraMaxH ballast with a ballast factor of 1.18. The ballast factor is important parameter to look for and determines the tube's drive current and light output. A lot of ballasts are sold as energy savers and have low ballast factors (like .87) they only drive the bulb at 87% of its rating, yes it saves energy but at the cost of light output. My GE UltraMaxH drives the tubes at 118% for more light. I am getting about 1000 LUX at 36" off the floor total power is 909W and if I want to save energy I turn several off. The 900 series phosphor is a nice broad spectrum brilliant white with a CRI of 90. I ended up with 24 T8 tubes arranged in three strings parallel to the 24' wall, one in the center, two midway to the wall on each side of center. The total cost for the bulbs, new ballasts and new sockets with shipping was around $300. This was less than one LED fixture. Glad I did the T8 and not the LED's, light is great, instant on, on hum or flickering, very happy with the results.
Got everyting at 1000bulbs.com
Tubes: Litetronics L-359 F32T8CB50
Ballast: GE UltraMax H part number 71723 (drives 4 lamps)
Sockets: Leviton 23351
Home center stuff is not your best choice for the best light output. Go for premium tubes and ballasts. One post I found suggested you buy cheep low cost fixtures without tubes. Then just toss the ballast and replace it with something really good.
Craig