Help Explaining this Transformer!

Hello Everyone,

I need a little help deciphering the plate on this transformer.

It is currently being used at our sod and stolen washing facility. We have 200 amps of 480 3P coming in. Everything is three phase except four 110V receptacles that rarely get used. My shop is about 125 feet from the electrical box where the 480 comes in. My shop has a separate single phase 100 amp service.



My thoughts are to replace the pictured transformer with a smaller unit to power the receptacles and move the pictured unit to my shop, I would like to use this transformer to replace my single phase service. I have a 10hp rotary phase converter for all my three phase equipment. I would eliminate the phase converter plus a meter and have plenty of three phase in my shop. To boot, 3P power is less expensive than single phase.

The single phase output, of the transformer, will easily handle my single phase requirements. What does the "208Y" stand for. Is it 208 three phase?

My 3P equipment is 220-240V. A couple of motors will are not capable of 480 three phase. Will I need another transformer for step the 480 3P to 220 3P.

After running the 3p to my shop I would convert a couple of single phase machines to 3P namely my air compressor. I am also looking for a good used TIG welder. To my understanding there are some bargains on 3P TIG machines. Home shop guys cannot power them and most businesses buy new.

I welcome any and all advise.

Thanks,

Grits

Well, there HAS to be a reason for that transformer.

The question is why that transformer is there in the first place? If all it powers are a few 120v outlets, you can easily get away with snagging that one, and putting a smaller one there. Anyways, what runs on 3 phase power at that washing facility?? Any pumps, or stuff like that?? Do they need 208/220 2 phase or 440v 3 phase?? If none of the 3 phase stuff is 208v, you can snag it. You will need to wire in a replacement transformer to supply enough current for the size of the single phase pannel. I don't think they'd put a transformer like that there if it wasn't needed. How many amps is the breaker box on the output of the transformer?? If it's smaller than a 120 amp, there's plenty of overhead. Remember, lights and stuff are probably 120v too.

Anyways, the output of that should work for your shop. Yes, 208Y is 3 phase power. Ask somebody to take a look at the stuff at the washing facility to see what they think.

If the transformer isn't loaded all that much, you COULD just run your shop off the output of it, and leave it where it's at. That's what I'd do if it's not too far away. Should be about the same as connecting your shop to the 480v.

Jyj

I know exactly what powers what. I built it. It is covered but open in the sides. We do not operate it at night. There is do much activity in close quarters. It would be very dangerous.

Every motor is 480 three phase including the well that supplies the water. Everything runs our of the three phase panel. The stolen (sprig) washer was built first. There are only five motors. One that powers a hydraulic pump, two large blowers, and a fractional motor that powers an injection pump that chemically treats the plant material plus a submersible well. The sod washer is similar but does not have the injection pump. There are two 480 3P receptacles that supply power for the refrigeration units for two sea containers.

The 110 panel has four breakers in it for the receptacles. The whole thing was designed and built in seventy one days. We actually shipped the first sea container seventy one days after we got the order. It is a long story. There is some info on my website, www.quailvalley.com. Originally, we thought we may need lights and a variety of other things were were not needed. To say the least, it was experimetal but it ended up working well. I will post a picture later today.

What does the "Y" designate?

I considered running the single phase to my shop from the transformer. In short, it is not needed at the washing facility. I will run three phase to my shop anyway. It would be more efficient to run the three phase to my shop and step it down there. I will replace the transformer at the washing facility with something much smaller.

Thanks,

Grits

"What does the "Y" designate?"

That the secondary is Y-connected, as opposed to ∆-connected, which is the usual case for the primary.

A 120/208 system implicitly requires four wires, A, B, C and N. Hence, a Y system.

Any of A, ..., B to N is 120. Any of A, ..., C to any other, except N, is 208.

Primaries are usually ∆-connected to avoid so-called "zero-sequence" currents, which cannot occur in an ungrounded ∆ system.

Another reason for using ∆ in the primary ... the high side ... is three-phase power can still be delivered if there is a temporary line-to-ground fault.

There is a Y version of 480 ... the now much more common 277/480 Y system.

You can deliver about a megawatt (1,000 KVA) using a 277/480 system, which is why it is preferred for new installations, and most particularly for commercial installations.

Heck, you can deliver 1,000 megawatts (1,000,000 KVA) using a 230 kV system, but customers seldom are connected to the transmission system.

OK, well, I didn't know what the deal is.

The Y refers to the way the coils are wired inside. You have 3 coils on the secondary, all tied together at one end. When you draw it on a schematic, it looks like a Y. The other end is each one of the output wires which are the tips of the Y. The middle wire is your neutral, which is bonded to ground. You get 120v single phase from any of the 3 tips of the Y to the middle. When you measure from the end to end, you get 208v. It's actually 220v, but because the phases aren't perfectly opposite each other, you get 208v according to a meter. You know how you have 2 hots inside a single phase breaker box, and a neutal/ground bar??? Well, in a 3 phase box, you have 3 hots, and a neutral/ground. Not much difference other than 3 phase stuff is expensive. You'd still be getting 3 phase power to your shop, it's just it would be wired to the output of the transformer, AND you wouldn't have to buy another transformer for the single phase plugs at the facility. Still doesn't make a lot of sense to move it unless you'd have to route the wires all funky over a long distance. Or, the cost of the fatter wire is greater because it has to carry higher current to your shop than the cost of a smaller transformer and the cost of the wire needed to carry 480v. Just trying to save you a bit of $$$. Both accomplish you getting the desired 3 phase power. The other benifit (besides cheaper wire) is if you ever got a machine that required 480v you'd have it at your shop if you move the transformer. The other problem is you'd need a 3 phase main breaker for 480v at your shop, as well as the 208v pannel. It's up to you, there are benifits to doing it either way, depends on what you want/need.

Pannel

JYJ

Running the smaller wire for three phase would be much easier. I also want 480 3P in the building for future use. I would imagine the transformer has a copper coil. It is outside. My luck with copper has not been good lately. This would be easier to steal than the wire from a submersible well.

As far as a three phase box in my shop, I would use a disconnect with fuses unless I found a real deal on a three phase breaker box. If I recall, the one in our washing facility was very expensive.

I am going to the farm shortly and I plan on shooting some images and I will post them.

Thanks again,

Grits

1) this transformer *could* be used to power the existing 120 volt receptacles at its
present location. Be sure they are being run by the separate service entrance before
removing it.

2) whatever the transformer is attached to, will stop working once you remove it.
Obviously you should trace out what it is hooked up to on the low voltage side.
Some of your motors at the present location might be 240 volt three phase, be
sure this is not true.

3) the transformer as shown will not provide 240 volt three phase. I can provide
120 volt single phase (phase to neutral) and it can provide 208 volt phase to phase,
three phase output.

Many load motors rated for 240 volts can be run on 208 in an acceptable fashion.
If you want you can include a buck-boost transformer to bring the voltage closer
to 240 volts at the output, this means including two small dry transformers in the
installation.

Star connected service is often used when most of the load is anticipated
to be at 120 volts.

Jim

Thanks Jim

I am one hundred percent sure all my motors are 480 three phase. Below, you will see some images of what I am talking about.




After giving it some thought, 480 will take care of all my three phase needs. My Nardini 1440E is the only kicker; however, I have a 5 horse Baldor Super E and a vector drive that I am going to replace the existing two speed motor with. The drive is 3P 220 and out. It would not be a big deal to sell the drive and replace it with a 480 in and out.

My BP, that came over on the Mayflower is being run by the above mentioned phase converter. I have a VFD I have been meaning to install for a year. It is a 1/2 HP machine and will run the drive with single phase 220. I have a forty year old wood cutting band saw that is 220 3P. I need be, I can replace the motor for a song. I may be able to be wired for 480. It The conversion will be a short term pain but a real convenience in the long run plus save me some money.

Thanks again,

Grits

Collard Greens

For you Southerners,

I can wash a pickup load of collard greens as fast as you can load them in the machine. Yall Yankee's most likely don't understand but collard greens are important. If you are in my neck of the woods and have a major mess of greens, holler and we will fire that mother up. Of course, I will need a small cut for my health and welfare.

Us southerner's could have a one hundred post thread on washing collard greens and a one thousand post thread on cooking them.

Another thing us Southerners have expertise in is ethanol production. The government just think there are not many experts in that field.

Grits