Checking voltage at a local library to troubleshoot led replacement lamp flicker ,found that the lighting panels are fed from a reduced voltage transformer. It is primary 208 delta to 102/176.8 y . I have never seen or heard of this and no one i talk to has either. Other general receptacle and appliance panels are standard 120/208 . Why would this transformer have ever been used?
Welcome to the forum. That doesnt sound right; the service to the building is 208y/120V, but this transformer is 208V delta? Sounds like a buck boost to convert 240 to 208 (or, here, 208 to 177), but it makes no sense to convert wye to delta back to wye, or to drop the voltage to the numbers you listed.
The xfmr sounds completely unnecessary to me but I dont know. Was the service ever at any point a high leg delta? Maybe the x-fmr was meant to boost 208 to 240 and is wired wonky?
I recall recently seeing a 4' LED tube that accepted an input voltage of 100-280V. Flicker can also be caused by tube/ballast mismatch. Are these 4' tubes, and are they wired off the ballast or do they bypass it and run on line voltage?