On Thu, 15 Oct 2020 18:37:57 -0700 (PDT), Bob D
wrote:

On Thursday, October 15, 2020 at 7:38:49 PM UTC-5, Clare Snyder wrote:
Just replaced 2 instant start ballasts and 16 tubes for a client
because all the lights in the office are the same - 2 tube pans in
dropped cielings - $210 in parts at my cost. Asthetics over economics
and I can understand that. To relamp the whole office with LEDs would
cost thousands -(50 units, +/-) and it's a rented office.

I am a fool when it comes to determining value based on cost. When I lit my shop, I wanted the brightest, most even lighting I could install with 5000k color. I selected 4" two tube daylight T5 fixtures. That was a few years back, but I still don't see LED fixtures that will compete with 10,000 lumens per fixture. I've replaced one tube and no fixtures. My shop feels like an operating room that has good light on every surface wall to wall.

Bob
When the ballasts start to fail you will see where replacing
flourescents doesn't make sense.
ANd a 4 foot T5 is optimistically 2900 lumens - nowhere close to
5000. Half that light goes up, requiring a reflector to direct it back
down while a good led light focusses ALL of it's 2000 lumens down
where it does you the most good. I've found replacing 4 tube
luminaires with 2 "tube" LEDs gives better visability.