I am currently in the process of converting our facility from T12 lighting to T8. I have four rooms with split 2 x 4 troffers. 2 lamps are on a dimmer. The dimmer is an old Leviton 6675 rotary switch that states that it is only to be used with Universal 502 or 550 magnetic dimming ballast. 502-A is what is currently installed. I am upgrading with Philips Advance Powerline Mark 10 electronic ballast. Question is, do you see any reason why I can't reuse the old rotary with the new electronic ballast? This is a hospital application and a newer deco style is not needed. Simple is better in this case.
Magnetic to electronic ballast dimming
- Thread starter jefferyc
- Start date
- Status
Afters hours of internet research, I think I've found my answer. Since the dimmers are 20+ years old logic says just replace the dimmers with a switch that is known to be compatible with the ballast about to be used.
FYI, the 6675 has four wires. Black, white, yellow and red. I'm assuming, line, neutral, dim high and dim low respectively. A non-contact tester shows red and yellow to energize after it is switched on. Research shows yellow or orange to be dim high. The rotary powers on dim low and this is confirmed by the fact that the red wire is the one going into the fixture to control the two lamps on the dimming circuit.
The Philips Advance Powerline Mark 10 is a two wire control. Line in and dim high. I believe that I could use only the black line in and yellow dim high wire on the old 6675 but why risk a new ballast. As I said before, the 6675 is 20+ years old. Why upgrade the fixture and leave the old switch?
I would still be interested in hearing other thoughts on this matter.
FYI, the 6675 has four wires. Black, white, yellow and red. I'm assuming, line, neutral, dim high and dim low respectively. A non-contact tester shows red and yellow to energize after it is switched on. Research shows yellow or orange to be dim high. The rotary powers on dim low and this is confirmed by the fact that the red wire is the one going into the fixture to control the two lamps on the dimming circuit.
The Philips Advance Powerline Mark 10 is a two wire control. Line in and dim high. I believe that I could use only the black line in and yellow dim high wire on the old 6675 but why risk a new ballast. As I said before, the 6675 is 20+ years old. Why upgrade the fixture and leave the old switch?
I would still be interested in hearing other thoughts on this matter.
peter d
Senior Member
- Location
- New England
If the dimmer says it's only compatible with one type of magnetic ballast, I'm curious why you're even asking. 
I would not expect a 20 year old T12 dimmer to be compatible with a T8 dimmer, especially after the advances in technology made with dimming ballasts recently.
Bottom line, use a dimmer that is listed for compatibility with the ballast. Seems simple enough to me.
I would not expect a 20 year old T12 dimmer to be compatible with a T8 dimmer, especially after the advances in technology made with dimming ballasts recently. Bottom line, use a dimmer that is listed for compatibility with the ballast. Seems simple enough to me.
If the dimmer says it's only compatible with one type of magnetic ballast, I'm curious why you're even asking.
Bottom line, use a dimmer that is listed for compatibility with the ballast. Seems simple enough to me.
peter, just so I will have a better understanding, would you mind sharing in detail the differences in a T12 and T8 dimmer switch?
for anyone else that might be upgrading old T12 dimmers, here is some good solid facts.
http://www.howstuffworks.com/framed...m&url=http://misty.com/people/don//f-dim.html
http://home.howstuffworks.com/dimmer-switch1.htm
http://www.howstuffworks.com/framed...m&url=http://misty.com/people/don//f-dim.html
http://home.howstuffworks.com/dimmer-switch1.htm
Robert Hutcherson
Member
- Location
- Pembroke Pines,Florida
Jeffrey,
IMO, I would contact the ballast manufacturer and query them as to the compatibility of the existing dimmer with the new ballast. I usually get the best info in this manner. Good luck with application.
IMO, I would contact the ballast manufacturer and query them as to the compatibility of the existing dimmer with the new ballast. I usually get the best info in this manner. Good luck with application.
K2X
Senior Member
- Location
- Colorado Springs
I worked on lots of dimming t-8 retrofits between 2000 and 2007 and the preferred ballast we used at that time was a series wired, (rapid start), with a low volt dimming control. Mostly in school assembly areas like gyms etc. The one thing that seemed critical with our installs was the 100 hour burn in time on the lamps. I'm the type that likes to get 10 up and then test them, and then another 10 and test. I couldn't do that with dimmers.
- Status