Search results for query: *

I have a six-way S&C Vista switch model 615. In this switch five of the ways have OCP, and one of them is not. Typically, how would the feeder connect? Would enter through a relayed connection or the non-relayed connection. I believe it can be either way, but Is there a typical or an advantage...

@che12345 thank you I appreciate your time and effort on this. This is your life and its ending one moment at a time.

@che12345 thank you! You seem to be the only one who understands what I'm asking. and I think we are close. All else being equal. All else being equal, how does the shape of a wire affect ampacity, and is their math that gets me from one shape to another? I will ask it another way. Let’s...

I am only saying bus bar to convey shape. It is not a bus bar it is a rectangular insulated wire. I am trying to determine the ampacity difference in 2 wires of the same KCMILL, with the same insulation installed in the same location at the same temp. All else being equal how does the shape...

@che12345 yes this is what i mean A square conductor that is 1 sq inch has a perimeter of 4 inches that same 1 sq inch round wire has a perimeter of 3.55 inches so yes %100 temperature/temperature-rise differs due to different cooling surface area is there a way mathematically to get from one...

If I had rectangular strips of copper that were not industry standard size so no ampacity table existed for them. How would I calculate Ampacity? It seems that trying to match a specific circular mill area in the standard wire is not accurate. I guess another way to ask is what is the ampacity...

I want 240 L-N Can i Ground X4 tie x2 and x3 togather and use X1 wire to the device would be x4=N and x1=L 240V L-N should work but the connection diagram is not showing it This is your life and its ending one moment at a time.

We run these calculations all the time, and while there is not enough information in your post to determine if your particular situation is "reasonable," it certainly could be. You would need to know the load factor, RHO values, and other values to assess the accuracy of your calculations...

I have 2 non-utility transformers (480-415/240) that are solidly grounded in 2 different buildings. Building A has a single aforementioned transformer Building B has the second aforementioned transformer and an ATS and the load I want to feed the 3phase 4 wire load with the transformer through...

any issues with this installation? [ol 1] I know that the disconnect would need to be labeled for different voltages. I Disconnect, XMFR, and Load are all located on the same steal light pole. I All fuses 600V class. I Disconnect and XMFR are within a foot of each other. Load is on top of light...

thaks thats what i needed i will review IEEE 1375-1998 thanks again This is your life and its ending one moment at a time.

can not find guidance in 70E or IEEE. This issue makes VERY little difference in the calculation BUT I still want the reference UPS 40 bats @ 12V = 480Vdc But Float voltage is 2.25V Per Cell so the actual voltage on the bus when maintenance is being done is 2.25 x 6 x 40 = 540Vdc I use the...

@oldfieldguy Agree Because I'm working from home and have too much time on my hands I looked up the referenced MCC Link CENTERLINE 2100 with ArcShield Technology Helps to reduce arc flash hazards and provide you with increased protection against internal electrical arcing faults...

@waross lowering fault current does not necessarily reduce the incident energy levels. in some cases, it can raise it. breaker or better yet fuse between the transformer and the MCC. but that really just moves the issue from the MCC to the lineside of the new Fused switch.

if this is a high loadfactor environment then conductor heating can be an issue. see Neher-McGrath calculations

Thanks for the response. I thought about that actually. The X/R ratio of this unit is about 9. Adding a resistance downstream (however small that may be) would only lower the X/R ratio on the circuit.

I have a generator for a project. in this example it is a 2000KW/2500KVA .8 PF and 480V so the full load amps @ 80% PF is 3007A However, if this same generator was running at unity power factor then the most amps that I could get from it is 2406A. The X”d for this unit is let’s say 10% This...