208V/120V 3 Phase Power Distribution

[@waynenocton]

I’m used to this, but recently I finally got to work around the 120/240 3 phase with the 208 volt high leg, that was really strange. People were so afraid of the high leg that they pulled the fuses to the high legs at the service disconnects, but that way it can never be balanced, so I’m using the high legs and one other leg for each and every 240volt device, then when everything is finally done and working, I plan to balance things using a clamp on amp meter. I’m not a licensed electrician, but I do what I can before calling in the electricians to check everything and fix any issues prior to inspections, saves my boss a whole lot of money that way.

[@derekc6713]

Thank you for the thorough explanation. Got a curious question and this always stump me. What voltage do you get when you are tapping this in a three phase breaker for this Y transformer configuration? whenever you use three phase, does your power goes up since there is a factor square root of 3?

[@themaddtitan9799]

Good stuff, thank you.

[@dc95811]

Thank you.

[@jhacklack]

Very cool

[@TofuInc]

It's actually less than 1/10 amp that's returning via the ground conductor. It's only the unbalanced current. If the primary side was wired as delta instead of star, no neutral connection would be used.

[@dc95811]

I see. So if only 1 leg had a load you would need the neutral. But you can do the crazy 3 way load balance thing where all the current is kept within the primary feeds? The same way it works here at 120V 3ph drop, the same applies for the substation feeding this part of the world like a big 3 rail breaker box at high voltage.

[@USMC1984]

The neutral IS a current carrying conductor.

[@user-fn9cs4dv8r]

your transformer shows 240/120 secondary, should it show 208/120 instead?

[@dc95811]

The 240V outputs on those transformers are not connected. 120/240 transformers are the most common manufactured. 208V only comes from 2ea 120V outputs that are out of phase by 120 degrees. 208V is a really bad voltage to be stuck with, I can't imagine transforming to get it, it's a poor man's 240V.

[@user-fn9cs4dv8r]

@@dc95811 i see , thanks!

[@takashitamagawa5881]

In our work plant we have 480V 3 ph and 208V 3 ph coming in from the street. We have to boost the 208V on our floor to get 230-240V that some of our equipment needs.

[@dc95811]

@@takashitamagawa5881 They sell standalone transformers that can shift your 480 or 208 to 240. We have a 3ph 208/480 stepup transformer installed in our garage to run the car lifts.

[@takashitamagawa5881]

I advocated having some 480V to 240V transformed power when we moved into our current facility but I was overruled. So we now have individual buck-boost transformers on the equipment that needs it. It's odd that the USA has the two different medium voltage levels.

[@GH-oi2jf]

The "delayed start" angle is meaningless. All three waveforms should start at the left side of the plot.

[@jae23iii71]

Nice video. I’m working on this exact set up for a friend. His set up from the power pole is feeding a 200amp disconnect from the meter. Now I’m curious I’d like to bring 400amps to upgrade so I can have 2 200amp sub panels. My question is…. Do I have to upsize the wire from the utility pole?

[@dc95811]

I'm no electrician, but I know everything to the right of the power meter is under the power company's control. Guessing yes. There is also the question of can the transformers handle the higher currrent? Would they charge you for the upgrade, or be happy since your bill would be hopefully going higher?? Give them a call.

[@USMC1984]

Any time you increase your load by more than what was designed at the time of installation you will need to contact the local power company and let them know what you are needing, depending on your load requirements they may need to step up the transformer. Anytime you are wanting to add a sub panel you need to have a licensed electrician at least design it for you, there are many intricacies that need to be done. If not insurance companies will not insure the property.

[@M3thodbombz]

You will need to upsize your service conductors. In residential homes where there are poles, the service drop comes down from the pole and splices above your house near a piece of rigid conduit. That splice done above the roof of your house can be seen from outside. That splice point all the down to your meter are your service conductors. A licensed electrician can pull the permit for your home and have it done.

[@uripiru]

Where is GEC ? grounding electrode conductor that goes to ground ( grounding electrode). I am not sure if your local code follow NEC.

[@dc95811]

It is kind of hidden in the video, but if you look close you will see the green ground wire being bonded to the neutral at the service disconnect.

[@adilaziz3948]

GG

[@highvoltage1979]

Your disconnect needs to be bonded to ground

[@dc95811]

The ground and neutral coming from the panel, are bonded to the neutral from the meter on the left. That junction is mounted to the metal of the box. What is missing? I don't do this kind of work. It is electrically correct.

[@jimellerman5686]

Uh...uh...uhhh....uhh...uhhhhh

[@dc95811]

Lol! Good one! Stuttering freak should learn to speak! Might as well make videos without sound.