The Most [INSERT ADJECTIVE HERE] Power System You've Ever Worked On?

[xptpcrewx]

I have probably mentioned it before so it is not a secret, but it isn't important to this thread.

Who knows, it might be related to another experience for this thread. Its a small world in power world.

 

[MyCleveland]

1. Let's start with basics... your bad logic and incredibly low standard of proof for deriving the power triangle. This thread has seriously got me wondering if you understand math: https://forums.mikeholt.com/threads/power-triangle-challenge.2562710/

2. Then we can move on to how exactly you personally "designed" and "manufactured" 13.6kV 30MW turbines. I call B.S.



3. Once you get past that, and if they are willing to participate, we can submit our credentials to a moderator to independently verify them and report back to this thread. If you are not willing to do that, then I suggest forever holding your peace. This isn't a pissing contest.

Some of your discussion topics create interest, but your ease to belittle people, I cannot say I have EVER seen this behavior from an engineer.

I thought the site was for sharing with others, NOT about how smart (AS#) you can convince us you are.

 

[xptpcrewx]

Some of your discussion topics create interest, but your ease to belittle people, I cannot say I have EVER seen this behavior from an engineer.

All my posts are started in good faith. Admittedly, I have a low tolerance for BS and misinformation. Maybe that's something I need to work on. But engineers are people too who can get frustrated and make mistakes.

I thought the site was for sharing with others, NOT about how smart (AS#) you can convince us you are.

I am not trying to belittle anyone or convince them that I am better. The argument arose from post #9 and #11. I am open to criticism, it just needs to be accurate.

 

[Fred B]

Dont have the high power experience most here seem to have so mine probably quite mundane. But a current one I'm into is really unique and the chief inspector and other marine guys I've been in communication with have been at a loss as how to get it done. Need 240V 60A shore power for a Tesla style boat, (yes I said boat) out onto an aluminum portable floating dock, 40-60ft out into the lake. And still meet all code requirements and restrictions. Each season dock has to disassemble and pulled ashore, in NE lake freezes over.

 

[electrofelon]

Ok Ill take a stab at it. There are actually two I have in mind:

1. A mill in Providence RI. The adjective might be OLD! This had a 600V ungrounded service. Wait, dont scroll down out of boredom yet, it gets more interesting. The Utility transformers feeding the building were sitting on the ground in a vestibule behind a locked chain link gate. They were big, about 5-6 feet tall, I dont know the KVA. Primary was underground 11KV (according to one of the lineman). IT was pretty cool in that vestibule, looked like a min sub station with racks and busbars on the wall, just a few feet behind the gate. The building next door was fed off that too. The building was a slow moving project with not much going on so the only thing the 600V did was run a transformer for work power and lights, and it also fed the elevator, which worked sometimes. I remember some of the guys would have to go to the roof top elevator room and push the contactor in with wooden stick sometimes. Yikes. At some point national grid started getting really uncomfortable with those transformers there, so they took them out and refed the building with a 600V pole bank, still ungrounded. Several years later, I finally got the go ahead from the owner to upgrade the service to a 208Y/120. I never did get paid for the job, about 16k mostly labor fortunately. OH well, it maybe almost worth the experience working on it.

2. My house! I have mentioned this before on this forum so likely some will remember. Several adjectives could apply here. Lets start with CREATIVE. I really price busted this. I take service at regular 120/240, then step it up to 2400 MGN. Wire is #10 CU 2 KV PV wire. That isnt the sketchy part, if you look into it, that wire has plenty of dielectric strength to run at 2.4KV. This goes 1900 feet to a transformer where the MV feeds out of the loop feed bushing another 600V to the solar system, and the 120/240 feeds the house. A couple funny pictures, Anyone who has done or seen any MV cable work will get a kick out of that small wire coming out of the load break elbow. And a part of the 2.4KV run that is tied to trees with some romex! Im really trying to get that last little bit buried (note its just the last 100 feet that is temporarily run in trees, the rest is buried).

 

[electrofelon]

Just thought I would add a short Corollary explaining the choice of wiring method on #2 and why So much 'creativeness". It was primarily cost. 15kv #2 CN primary isn't that expensive (pre covid price about $1.90/ft, but it's really overkill for a single dwelling and thats the smallest size made. That PV wire is .30/ft (two runs needed of course, the grounded conductor could have been only 600v rated but I used it for both). So at 1900 feet, that's quite a bit cheaper.

But perhaps more importantly, I have a mini trencher that makes a 1" wide trench which is the perfect size for 3/4 pvc, so there was a strong incentive to stick with something that would fit in 3/4. 2.4 kv was used because of the availability of pad Transformers. Could have, but didn't want to order custom 2kv units. Another option in wire that is a bit more expensive would have have been 5kv L-824 airport lighting cable, which is essentially the same thing as that PV wire but with thicker insulation (and only goes down to #8).

 

[Jraef]

I am currently working on a project where we are retrofitting a bunch of diesel powered blowers at a turd farm to be electric powered using VFDs. There are all 4160V, 6 x 2,000HP and 2 x 4,000HP. The 4,000 HP ones will be the biggest VFDs I have personally ever started up, probably some time in December.

The biggest motors I have ever worked on were 15,000HP 12.47kV on some pumps for a NYC wastewater plant, I worked fir the company that made the Solid State Soft Starters and was on the team designing and testing them. We were the first to get UL listing for 15kV class soft starters at the time, so part of the project was getting that listing first. That was a much more interesting experience than the actual start-up, because it involved a destructive test at the end. I watched the unit basically melt down in the fault testing, with molten aluminum and copper running out of the bottom of the enclosure. Very cool.