mshields
Senior Member
- Location
- Boston, MA
We are putting together the specifications for a Central Utility Plant (CUP) that will be put together by the vendor in a turn key manner.
I appears we will need to provide a 13.8kV to 480Y/277V, probabably 1500kVA pad mounted transformer outside of the CUP in order to bring the required power out to it. This pre-fabricated building will be comprised of 3 large chillers, two cooling towers and all the pumping required in between. Our spec calls for 18 pulse VFD's abnove 50HP but nothing special below that, which I assume means, we would get 6 pulse.
I'm wondering how to best assure an acceptable level of harmoinics and an acceptable PF. Should I be specifying for example:
* 12pulse for a range up to and including 50HP?
* Should I extend the range to include 50HP and possibly below that for 18 pulse drives.
* Do I need active Power Factor correction via a switched capacitor bank?
Thanks,
MIke
I appears we will need to provide a 13.8kV to 480Y/277V, probabably 1500kVA pad mounted transformer outside of the CUP in order to bring the required power out to it. This pre-fabricated building will be comprised of 3 large chillers, two cooling towers and all the pumping required in between. Our spec calls for 18 pulse VFD's abnove 50HP but nothing special below that, which I assume means, we would get 6 pulse.
I'm wondering how to best assure an acceptable level of harmoinics and an acceptable PF. Should I be specifying for example:
* 12pulse for a range up to and including 50HP?
* Should I extend the range to include 50HP and possibly below that for 18 pulse drives.
* Do I need active Power Factor correction via a switched capacitor bank?
Thanks,
MIke