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Fuse 14.4KV 1.743MVA Maple syrup Producers

Fuse 14.4KV 1.743MVA Maple syrup Producers

Fuse 14.4KV 1.743MVA Maple syrup Producers

(OP)
I have to select the right fuse for an electric distribution line that feed 13 Maple syrup Producers, i went to every pumping station to check engine MSDS Sheet and other electric equipment to get the exact consumption in KVA of everybody. Now, after my search 1.743 MVA on a 1Ø 14.4 KV 121A electric distribution line conductor 2 ACSR 6/1 NU SL. I Know that they only consume 2 month per year February and March but its at full load 100% electric equipment works at the same time.  The line is mostly inductive, there are almost just electric motor but PF is 93.1% so its pretty much good. I know that i have to consider the start current of the motor especially because there is a lot of chance that they all start at the same time. Can you help me to choose the right fuse for my purpose?? thank you

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

Quote "Now, after my search 1.743 MVA on a 1Ø 14.4 KV 121A electric distribution line conductor 2 ACSR"

Wow. 121 amps is a lot on a single phase line. It make it hard to balance your system. The max fuse size is determined
by what size will coordinate with your substation breaker. You need to determine just what size that is. Suppose the max is 100 amps. You won't be able to fuse it. I would suggest that you add 2 additional phases to this line and balance the load. That would give you 40 amps per phase.
By the way, #2 is rated at about 180 amps.

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

(OP)
I dont understand 'Suppose the max is 100 amps. You won't be able to fuse it.' why??  i have one main fuse for all the producers but i have additional fuse for each extension of the line. example 13 producers on the main fuse, after that you hit a fused extension of the main line that feed 3 producers, you continue on the main line and you hit another fused extension that feed 4 producers, after you continue on the main line you hit a series fuse that feed 2 different extension each are fused one have 4 producers the other 3, each station got his one transformer with a fuse, is gonna be easy to understand with my draw
http://files.engineering.com/getfile.aspx?folder=0aa03888-3e18-4b36-8035-6755d297349a&file=coqui.JPG
the setup that i show you is the existent setup of the line and fuse can be add or replace or move, is that fusable or i really no to go 3Ø?

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

You have to consider not only the load on the fuses, but the coordination between fuses for a fault.

Let's say you have 5000A fault current at the tap to 4 producers and you figure 10A per producer.  If you put in a 40T fuse at the tap, then the next fuse up has 7 producers.  If you consider load only, you might put in a 65T fuse.  If there is a fault on the tap to the 4 producers, the 65T fuse will be damaged before the 40T tap fuse clears the fault.  For any fault over 3800A, you would need a minimum 80T fuse to coordinate with the 40T tap fuse.  If the fault current was over 6100A, you would need a 100T fuse to coordinate.  

You can get a table for fuse coordination from Cooper Power Electrical Distribution - System Protection Manual.
 

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

Cauchons Quote "I don't understand ''Suppose the max is 100 amps. You won't be able to fuse it.'' why?? "
I was not clear with my statement. What I meant was that suppose the max fuse under the sub breaker was a 100 amp fuse, then you would not be able to fuse the 121 amp load.
You need to determine what the max fuse size is under the sub breaker. Usually I would install the max size fuse. If you install a fuse that's to large, you could trip the breaker with a fault instead of blowing the fuse. As I said, I think you need to add 2 more phases and fuse the taps. Looking at your drawing, you are showing a symbol for a generator. Is your source a gen or a substation?

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

Cauchons
On you drawing, you are showing fused taps and fuses in the main ckt. Do you have the transformers fused? If so how do you determine what size fuses to use for the transformer?
You show a fuse close to the source and another about half way down. Are these actual fuses?  

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

(OP)
i am now drawing a better schema of the line so that you can see the real thing, tomorrow i will get you a good drawing. My source is not a gen i made a mistake in symbol not enough time to draw something good today excuse me for that poor drawing. My source is a 3Ø in 477AL after the 3Ø i have a fuse switch that go to an electric meter than go to another fuse switch and after the private line to every producer, i dont have a substation with breaker, everybody have their own electric drop with their own breaker, all user have 200A breaker before electric panel some have 1 X 200A some 2 X 200A and one got 5 X 200A. for now i give you the drawing of the line the source is at the middle bottom of the drawing i draw fuse and give you that after.
thank you very much for your help

ttp://files.engineering.com/getfile.aspx?folder=c9b7a3fe-412d-4f55-9185-c1f7cf2b5b73&file=Carte_Réseau_d'énergie.JPG

RE: Fuse 14.4KV 1.743MVA Maple syrup Producers

(OP)
Green triangle = pump station of the maple syrup
Red Square = Principal pump station
X = Transformer  

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