Hello, I am a new member and have enjoyed this site as a resource in the past. I have site that has me baffelled. And open to suggestions.
The site is a 2 year old complexe with three buildings. A memory care facility, this complex is fed by a Wye transformer to a 1600 amp main. There are multiple sub panels in each of the buildings. In the first year the building expierenced multiple failures and it was not helped by the poor wiring done by a now bankrupt contractor. As example, covers were pulled off and labled breakers were not in use so possible unbalanced loading was possible early on. Everything is Romex.
Since the start; half the electronic ballast lights have been replaced, the Arc Fault breakers trip without anyone in rooms, emergency lights register a power failure, UPS units do the same, currenly about 90% of the electronic thermostates on PTAC units have been replaced, two fire alarm power supplies, low voltage lights go out 5-6 at a time. The part we work on is the elopment system and the tag receiver by the doors scramble and need to be reset. (RS485 and RF) Other low voltage units with simple logic have needed power cycles or replaced. When entering the building a radio in the 120mhz area breaks squealch.
Suspecting Harmonics a power quality test was done and ten min. averages were as high as 19.9%THD, but the testing company does not think that is out of the norm considering the electronic lights. The complex max current draw for the testing period was 524amps and the neutral wire had 123amps. Again, they don't think that is abnormal or an issue.
Any Three Phase experts or Harmonic experts agree? Thanks for input.
The site is a 2 year old complexe with three buildings. A memory care facility, this complex is fed by a Wye transformer to a 1600 amp main. There are multiple sub panels in each of the buildings. In the first year the building expierenced multiple failures and it was not helped by the poor wiring done by a now bankrupt contractor. As example, covers were pulled off and labled breakers were not in use so possible unbalanced loading was possible early on. Everything is Romex.
Since the start; half the electronic ballast lights have been replaced, the Arc Fault breakers trip without anyone in rooms, emergency lights register a power failure, UPS units do the same, currenly about 90% of the electronic thermostates on PTAC units have been replaced, two fire alarm power supplies, low voltage lights go out 5-6 at a time. The part we work on is the elopment system and the tag receiver by the doors scramble and need to be reset. (RS485 and RF) Other low voltage units with simple logic have needed power cycles or replaced. When entering the building a radio in the 120mhz area breaks squealch.
Suspecting Harmonics a power quality test was done and ten min. averages were as high as 19.9%THD, but the testing company does not think that is out of the norm considering the electronic lights. The complex max current draw for the testing period was 524amps and the neutral wire had 123amps. Again, they don't think that is abnormal or an issue.
Any Three Phase experts or Harmonic experts agree? Thanks for input.