EEJaime,
Your last two lines is a local joke to all of us, it is a city owned electric utility. Long story. Anywho I have dropped the transformer down to a 500 kVA and the poles in between fields are single poles, there will be a total of four between the fields. Thanks for your input.
I am in the middle of a study at our utility and there is a good forum called arcflashforums.com that will give you more info than you want. Every piece of equipment on your system is not what the law says. It mentions everything over 125 kVA and above 208 volts I believe (could be wrong on that...
Here is a .pdf of the file that was attached in the previous post.http://files.engineering.com/getfile.aspx?folder=25deb67b-f9f1-43e3-b05c-e8ecb587331b&file=fields.pdf
EEJamie,
It appears that the poles to be used are prewired with a terminating box 10' off the ground. This box has a two pole breaker in it in which we are going to run a two wire 480 plus a ground into. This will lead us to have to hook it up as you mentioned in the last part of your post. The...
The lights are 480 volt and my impression is single phase from the supplier. We are looking at setting a 750 kVA 13200:277/480 volt pot to feed all these lights and consession stand.
The lighting manufacturer gave us a amp draw of 22 amps which figures as I have shown above. I just don't see...
Our city is building 4 soccer fields and putting four poles per field with 11-1500 watt lights per pole at 480 volts. The fields are shaped in a rectangular fashion with a pavillion in the middle of all fields where the transformer and controls will be located as well as a consession stand. In...
I didn't take the time to ask the question the right way when I wrote it. Should have proofed it.
The question is all three being overhead pots, normally we hook the up with the H1 bushing the hot phase and the H2 back to the neural, this is done for all three pots. If you were to hook up the...
The "hot" phase I am speaking of is the 7200 volt to ground phase which one connects to each overhead transformer in the three phase bank. Sorry if I was unclear.
Does it matter which bushing you tie to the hot phase on a WYE hi side? In a delta, doesn't it create a phase shift if you reverse some connections on the high side??
I am trying to learn some more about fault and fault currents. If a utlilty has a known fault current on the high side of a power transformer (161kv) of x amount of amps three phase. With the nameplate information given (kva,voltage,impedance) what is the forumla to determine the fault current...
I agree with lansford, tie it to a gps grid, the only problem with that is systems like mine don't have that technology yet and are understaffed if we did have it, so we keep doing it the way we have forever.
Nah we don't require renumbering cause we have line names and pole numbers, so in the event of changing sources we just go by the line name and pole number up to a particular open point and nothing changes.
