Not afraid to admit i don't know everything

Status
Not open for further replies.
C

Chase08

New User
Location
Augusta Georgia
Occupation
Residential/ Commercial Electrician
So I'm 24 years old. I have been doing residential electrical new and old construction for 9 years now. I have done commercial for about 6. All but one of my commercial work has been remodel. One thing I have never done is convert a 208 line. I have to start Monday and finish Wednesday. Being my first time wanted some knowledge. Where do I get 208 opposed to 240 on 3 phase? Doesn't thus require a transformer
 
sqrt 3 * 120 = 208

convert 208 to 240 = auto xfmr needed e.g connect 240 V range to 3 phase without loss of ability to boil water quickly.

good to admit lack of knowledge, but question does arise as to what the last 9 years have been since you were 15 YO? I think my high school physics class at least made folks aware of phase. Or was question just very poorly worded?
 
I'm not sure exactly what it is you mean by convert a 208 line. The reality is none of us knows everything there is to know about anything much less everything about everything, unless one is a moderator. Then one is omniscient. :)

My guess is you're going to find that if you need a three-phase 208 to 240-volt transformer you're going to have a very difficult time getting one by Monday. Just about everything these days parts-wise is hard to come by.
 
It always pays to use a meter and know what are the possible types of service. In my area it is unusual to see a three phase 4 wire (high-leg Delta) 240/120 service. Three phase 208/120 is much more common.

So chances are you don't need to do anything special to get 208V. Just use a 2 or 3 pole breaker in the panel. But do measure first.

Sorry if this wasn't the question asked.
 
You need a transformer to get 208 to 240. Depending on the system the power company has you may get them to change out the trany. I am not certain if you want 208 and have 240 or vice versa
 
You have a 208/120 Wye system now and you need 240?
Single phase load or three phase?
Typically buck/boost transformer(s) for a single load. Fairly common and inexpensive for the most part.
You will need to know the current of the load to size the transformer(s).
More involved but doable if you have Line to neutral load as well.
 
I hope you don’t mean you have 240/120 single phase and you want 208/120 3 phase. That’s a no go. You can use a rotary phase converter to go from 240/130 to 240 high leg for motors, or get the utility to add a transformer in a full or broken delta for 240 high leg.

But 240 three phase to 208 three phase makes no sense whatsoever. 208/120 only exists to run a lot of single phase loads with a small amount of services like HVAC and pumps like commercial office space. Almost all 200 V class equipment is designed to operate on 208-240 because both are around.

You can put 240/120 transformers on a 240 system on the third (non-split) leg too.
 
Chase08 said:
Not afraid to admit I don't know everything. I'm 24 years old.
Click to expand...
This made me laugh. I'm still chuckling as I write this. If you make it to 100 years old, you still won't know everything about this trade. Nobody does. It's a vast trade with lots of specialties. I would be surprised to hear somebody say they know everything about the one specialty that they have been doing for 40 years. There is always something you haven't learned yet.
 
Coppersmith said:
This made me laugh. I'm still chuckling as I write this. If you make it to 100 years old, you still won't know everything about this trade. Nobody does. It's a vast trade with lots of specialties. I would be surprised to hear somebody say they know everything about the specialty that they have been doing for 40 years. There is always something you haven't learned yet.
Click to expand...
Yes but often people around his age (and wives of any age) often think they know everything ;)
 
Not knowing everything at 24 is just fine. But if you don't know everything at 16 then you are weird :)

Seriously, knowing that you don't know and asking questions is the key to wisdom.

I don't quite understand what you are asking in your question. 1) Do you need help figuring out where the 208V comes from when you have two 120V lines, or 2) Do you have a 208V line where you need 240V, or 3) Do you have a system where you sometimes get 240V and sometimes get 208V or 4) Do you have a 240V line where you need to get 208V three phase, or 5) Something else?

Best of luck
Jon
 
Status
Not open for further replies.
Top