Multiple luminaire pole system existing with ground rod at each pole. Primary utility service overhead 120V (two conductors only) then run underground in PVC conduit to the poles. Scope is to provide a new camera at each pole, and to provide a bonding conductor between the camera equipment...
Utility transformer 13.2kV-480Y/277V (wye-wye). Enphase inverter output 208Y/120V; have in-stock a 45kVA 208Y/120V-480V delta transformer.
For a normal generator, would assume we would not parallel services; however, the inverter sine waves are controlled by the utility, so would they even care...
Rooftop PV system approximate size 2MW. Weather station had a lot of signal errors which were blamed on the DC cabling causing interference. Grounding was correct. Cable was installed in PVC, unshielded, and run with 120V power cable approximate distance 150 feet. Problem was solved by...
Where can I find samples/equations to calculate planned and unplanned outage rates for a utility-scale PV system? Are they inside an IEEE standard? Have seen them for nuclear (much more detailed) but not PV.
Multi-tenant (nine meters) warehouse, fed 240V-delta. Three customers use the 240V three-phase service, remaining customers use the 120/240V single-phase service. Three single-phase customers plan to install PV using 240V single-phase inverters.
Installation is allowed per NEC 690.63(A)...
We have a large, non-metallic hard case to house the PP4300, CTs, VTs, power supplies etc., but need a small hardcase that will house a single PP4300 that we can drill holes in for probe and power supply entry. Also would like ability to attach an aircraft cable and padlock to the case.
Anyone...
480V, 3W system. Equipment bonding conductor sized per the overcurrent device. Running 3-1/C#2 and 1-1/C#8 GND from source to building via ductbank with handholes. Do we have to bond the rebar in the handholes to the bonding conductor? How could you / is it necessary to ground a metallic cover?
Given:
10 MVA, 46 kV - 12.47 kV Transformer
Z = 10.4%
Primary Tap -2.5% (45 kV)
Secondary Tap +5% (13.09 kV)
3P Secondary Short Circuit Current = 4290 A
1P Secondary Short Circuit Current = 4620 A
I am trying to determine the utility (primary) short circuit contributions but seem to be missing...
Aside from miscoordination, are there negative effects associated with series connecting two TVSS systems? For example, plugging a UPS with TVSS into a power strip with the same level of TVSS or higher.
I am trying to locate an online course that will teach basic electric power principles to our CAD operators. There are many books available, but I prefer to have online training coupled with workbook-type materials. Any suggestions would be most appreciated.
