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3000 amp ATS Swap

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The Beast


Labeling existing cables



My handsome and portly self with Carlos, our client and Garden Nome



Each of the 96- 500 MCM cables recieved a unique three digit number. Starting with Emergency Neutral One, (EN1) all of the way through Utility C Eight (UC8) It took an hour or so for a couple of guys to mark them. I only had to be QC on that one.



Ok, You took them off, you put them back on...



Yup! Its upside friggin down!!
This is how the customer save thenselves a couple of bucks buying it themselves and not consulting with me about WTF they need.



96-500 MCMs on the wall, 96- 500 MCMs, Make one up, torque one down, 95- 500 MCMs on the wall... all together now!



2- 500 MCMs on the wall, 2- 500 MCMs. Make one up, torque one down, 1- 500 MCM on the wall.



20 hours later and about 120 OT man hours. We get the door to close.
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Discussion Starter · #4 ·
For that start up, I used the generator first.
I was very confident but, we were dealing with 15 year old cables and handling them off of the terminations. I mitigated every problem I could but could not megger them out due to the controls from the generator and utility breaker.


I first placed the generator power on the switch closed to utility to check out the emergency side terminations.
Then I opened the generator breaker and closed the switch to emergency side to test the load side terminations.
We closed the generator breaker AND,
No explosion! that was a good thing.

I used the generator to test the load side only due to the very low short circuit rating, maybe only 20kaic, as opposed to the utility which I believe could have been at least 100 kaic or maybe over 200kaic right out of the vault, 5' away.

I opened the generator breaker to take power off of the switch.

Then I closed the utility breaker.
No explosion on that side either. :)

The load side conductors of the switch had been tested with generator power all of the way into the opened MDP. All switches open there of course.

Next was to open the utility breaker and close the switch to utility.

Once the switch was closed to utility, I then closed the utility breaker.

Lights lit, the band played and we watched the sun come up on the way out of the parking lot.



Not a perfect and completely safe way to get something like this done but, very practical.

Hammer away guys. :whistling2:
 

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Discussion Starter · #5 ·
Did you replace just the mechanism within or the whole enclosure too? What happened when you found out the configuration was wrong?
Just a gut swap. We do these all of the time.
This one was interesting just due to the very large size in that frame.
Usually they are broken up into smaller 1000 amp switches as not to have everything in one basket.
The original install was a retrofit. with some genius using a 4 pole switch. :rolleyes:

The replacement switch was shipped with the lugs facing down.
It wasn't really easy to see how the switch was configured just be looking at the front of it.
Certainly in retrospect I should have inspected it better but it worked out.

I would have been much better off terminating the switch the way it was configured but that would have added maybe 8 more hours cutting back some conductors and crimping extensions on the short ones.
That and just the risk of mixing up even one cable was not not worth it.
 

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I did one recently at a chicken hatchery where no generator existed before. What a pain in the ass. (64) 500 kcmil spliced in the switchgear and taken to the transfer switch. Then (64) 500s back into the switch gear. What a crowded mess. I wanted to use locomotive cable but couldn't budget the cable or lugs.
 

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As I get more involved with generators, I have to be mindful of the size and weight of these items. The biggest I have worked with was 600 amp and that was heavy, nothing compared to what you have there. Having enough guys to hang these items, will it fit, do I do have enough space to wheel it in there? All things to consider.
 

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Discussion Starter · #9 ·
As I get more involved with generators, I have to be mindful of the size and weight of these items. The biggest I have worked with was 600 amp and that was heavy, nothing compared to what you have there. Having enough guys to hang these items, will it fit, do I do have enough space to wheel it in there? All things to consider.
Planning is paramount.
I take lots of pics, measure and plan every inch of space.
We had to move the mounting forward one inch. One ding dang inch to make it work.
Two inches and one of the terminal blocks on the front would have hit the door.
 

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Discussion Starter · #10 ·
I did one recently at a chicken hatchery where no generator existed before. What a pain in the ass. (64) 500 kcmil spliced in the switchgear and taken to the transfer switch. Then (64) 500s back into the switch gear. What a crowded mess. I wanted to use locomotive cable but couldn't budget the cable or lugs.
Thats quite a but of cable to deal with.
I put inspection holds for myself along the way just to make sure nothing bad gets by.
 

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First try at an album:

The Beast


Labeling existing cables



My handsome and portly self with Carlos, our client and Garden Nome



Each of the 96- 500 MCM cables recieved a unique three digit number. Starting with Emergency Neutral One, (EN1) all of the way through Utility C Eight (UC8) It took an hour or so for a couple of guys to mark them. I only had to be QC on that one.



Ok, You took them off, you put them back on...



Yup! Its upside friggin down!!
This is how the customer save thenselves a couple of bucks buying it themselves and not consulting with me about WTF they need.



96-500 MCMs on the wall, 96- 500 MCMs, Make one up, torque one down, 95- 500 MCMs on the wall... all together now!



2- 500 MCMs on the wall, 2- 500 MCMs. Make one up, torque one down, 1- 500 MCM on the wall.



20 hours later and about 120 OT man hours. We get the door to close.


:yawn::yawn::sleep1:























:jester: Seriously, looks like fun :) What does this power btw?
 

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How did you calculate 100/200Kaic?

3000A @480v equates to a 2.5MVA transformer.
A transformer of that size will have a reactance of 5%+. At 5% using the “infinite source” method works out at 104.16KA, given system impedance it will be well below that.

How were the singles cleated once installed? Magnetic repulsion is very powerful.
https://www.youtube.com/watch?feature=player_detailpage&v=HmnrJa7Zk0A#t=84s

Ft = (0.17 x Ip²)/S
Ft = Maximum Force per unit length of cable (N)
Ip= Peak short circuit current (KA)
S = Centre to centre distance between neighboring conductors (m)

A fault will force the singles to violently throw apart. This caused the death of an electrician when trench covers were thrown in the air due to a heavy fault current on nylon strapped singles.
 

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Discussion Starter · #20 ·
How did you calculate 100/200Kaic?

3000A @480v equates to a 2.5MVA transformer.
A transformer of that size will have a reactance of 5%+. At 5% using the “infinite source” method works out at 104.16KA, given system impedance it will be well below that.

How were the singles cleated once installed? Magnetic repulsion is very powerful.
https://www.youtube.com/watch?feature=player_detailpage&v=HmnrJa7Zk0A#t=84s

Ft = (0.17 x Ip²)/S
Ft = Maximum Force per unit length of cable (N)
Ip= Peak short circuit current (KA)
S = Centre to centre distance between neighboring conductors (m)

A fault will force the singles to violently throw apart. This caused the death of an electrician when trench covers were thrown in the air due to a heavy fault current on nylon strapped singles.
Just a WAG.
 
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