I have a number of twin 6ft T8 70W fluorescent fittings and have been offered a number of Osram Quicktronic 2x 80 watt QT-FQ electronic ballasts which are relatively new.
Will QT FQ 80's work with 70W tubes?
(The reason for asking here rather than simply trying them is that they are some way away and also will take some time to remove from their present rather inaccessible location so I'm rather keen to have some confidence they will work before collecting them!).
Running mismatched tubes/ballasts is generally not a good idea. How a ballast behaves when running out of spec is not defined, and could cause overheating/fire/etc. Even if it appears to work, it might not handle end-of-lamp-life correctly, and could break the tube or overheat the tube caps if it carries on trying to run it. Finally, test it on a power meter and check the actual power draw, and the temperature of the tube and ballast in operation.
A 70W tube is a T8, and the 80W tube is a T5HO. You'd need to find the tube ratings and compare them. The 80W tube is
530mA/152V. Ratings of T8 tubes is complicated because of their history. They were designed to run on ballasts for T12 tubes, and consume less power, but they have to be safety rated for the full power of the T12 tube they replaced, and on electronic control gear they are underrun so the lamp+ballast power is less than the lamp power rating.If the QT FQ is a digital ballast, and especially is it's one designed to drive a number of different tubes, then there's a chance it may mis-identify the tube and run it at completely the wrong rating, or refuse to drive it at all.
There's a reasonable chance it will work, but it's not certain. I would try and get one to test with first. Even if it does work, it might be fine for your garage or attic, but I wouldn't install on someone else's premises.
It is a slightly older unit designed for one tube (80W T5HO) .
The problem is that to get at them involves assembling a frame Noah used for building the Ark. Once that's up I may as well get all as get one!
They would all be used in my own garage/workshop.
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.