L1 is either intentionally or accidentally grounded. If intentionally, it should be treated as a neutral.
Hold on, what is this "neutral" you are measuring to?
Read up on corner grounded systems. They were common back in WWII plants. Not too many still in existence today.
There's 4 wires red black blue and white and everything is working it's just really confusing me. So what would I do with the neutral if I treat the other as a neutral and wouldn't I have to track the circuit to see how it was used in other systems. There's 3 wires going to the contacts red black and blue or sometimes white. Are they interchangeable. Also why don't I get 480v when I test the two 240v lines together like you do when you test two 120v lines. I also looked at our transformer coming into the building there is only one hooked to three primary poles and each one has their own little unit attached to the outside of it looking like there's one each attached to a primary in series.
It is connected to the neutral bus that in some parts of the plant are connected to the ground also it's like they use the blue and white wire interchangeably
As stated above, it’s a corner grounded bank.
That's where I was going, my answer was going to be, who cares. But you may have reason to care.
I get 240v from line 2 or 3 regardless if I test from the line one to 2 or line 1 to 3 or line 2 to the white taped wire hooked to the neutral bar or line 3 to neutral I still only get 240v hot line 2 to hot line 3 instead of 480v unlike in residential when you measure the two 120v lines and get 240v. I'm assuming the two 240v lines are 180 out of phase that's why it still reads 240v across both the hots unlike the two 120v lines in phase. If the two 240v lines were in phase I'd get 480v right
I agree with the others your voltages sound like a corner grounded system, but it doesn't seem to be set up right. Corner grounded system should look like single phase, but your service conductors consist of four wires? Can you see what happens to the white wire as you trace it upstream to the utility transformers? Could be you have two grounded conductors.
The lighter is a 100 and the teaser is a 50. Everything is fine right now, but they are still building out the building and adding things, and one floor I don't even have a plan yet. I'll just keep an eye on the loading and see what happens. The reason I am caring more than I normally would about this one is upgrading the service would be really problematic. There is just not room for a vault and even adding a pole would be very difficult. The existing serving Pole is a fair ways away and the conduit goes under the street which then enters the building under a concrete ramp. On top of that the meters are inside which they do not like, and I'm nearly certain they would make me move the meters outside to do any changes to the service. The service lateral is a single set of 500 AL which is sized about right to those transformers so they probably can't really upgrade the transformers without upgrading the lateral. On top of all that, I just not sure I have the energy right now to deal with Seattle City light
Ok. I know there are a couple of posts after this, but..
Sounds like normal corner grounded Delta operation.
Could be the 4th was for fault management on an ungrounded delta. But that wouldn't explain a 0V to ground on L1.
I am unsure what this system really is. I am leaning towards an unintended grounded system
It does but.
I was told this is a ungrounded system cause of chemicals and gases being used so the process isn't interrupted and this building was built in the 1930s. That being said L1-L2 240v L2-L3 240v L3-L1 240v L1-N? 0-5v L2-n 240v L3-n 240v and that's it only 4 wires 3 black a fourth black with white tape on the end connected on the only bar on the right side. This is the only place I see 4 wires in the control panels there's only 3 black wires numbered 1 2 and 3 or two are marked with red and blue tape on the end being a black red and blue. It seems no matter how I test I only get a 240v reading or 0-5 on the L1-N. I've only done residential and they really only taught us 480v in school for industrial maintenance and other places I've worked were all 480v. I'm just not familiar with this type of system and want to know if I should worry about it at all and just treat it like any other 3 wire system I was just wondering if there was anything I needed to know about this configuration when wiring motor starters controls and stuff and why don't I get 480v between the two 240v lines shouldn't the two voltages combine or does that have something to do with being in or out of phase. Sorry I sound like a idiot but I've only been doing the industrial side for a couple years and this is the first job I was hired as a electrician and to make matters worse I'm the only one on a 3 man maintenance team that has any electrical background at all I would just feel better knowing what kind of system I'm dealing with so I can further educate myself so I can be a valuable member of the team. Thank you.
