WHY, 3W Delta 480V instead of 4W Delta 480V?

[Joethemechanic]

I’ve been around hundreds of industrial machine tools, and I’ve never seen one that required 240/480. Anything that ran on 480 required only 480.

Almost everything I've dealt with had 240-480 motors on them. If anything the problem has to do more with contactors, discos, and other control circuits.

Sure I see motors with only single voltage brought out, that can kinda suck too, lots can be wrong.

But everyone I know with a mom and pop business with 208 wye, like a garage, machine shop, wood working, whatever. They always end up with lots of b/b transformers everywhere.

In PP&L land they only offer it to legacy customers anyway, so all the new services are 208, or 480

 

[retirede]

480 / 240 motors. as in 480 or 240
But not both, delta/ wye motor windings.
I am not sure I have ever seen a 480 anything that needed a neutral?
I have seen lots of 277V lighting.

Correct. Most machines could be ordered in either voltage. When built for 240V, the motor controls, wiring, and disconnects had to be upsized accordingly. Control voltage (120V) supplied by integral transformer.

 

[tortuga]

@11bgrunt it says you work on the utility side, and here corner grounded was a common for a long time, a '3-wire' 240 or '3-wire' 480 service.
Was typically for pumping of water, sewage and oil/gas. For new service corner ground is not recommended the why is because of wye;
With the world now all moving to Variable Frequency Drive (VFD) technology, even on old pumps, the VFD's require, or specify a wye configuration dont ask me why, I honestly do not know and found the whole requirement silly at first.
VFD people are very particular. There are many on here that will correct me if I am wrong. I am no VDF expert. I do just meet the requirements and often.
So many corner grounded services are either converted to wye on the customer side via drive isolation transformers (with 24/7 losses) or the customer gets the utility to install a 480/277 wye bank.
Unfortunately there is a extra wire required by the NEC in the service lateral/ service drop even if its a wye service with only '3-wires' used, (fault clearing path) so often the drive isolation transformer is up front a cheaper option and keep the utility side as is.
the other issue is 240 corner grounded delta converts to 208y/120 but as some say 208 is too low, or out of spec, see the 120 is discarded nobody cares about 120.
So some have a hard spec for 240V so '240Y/139' (I think a utility can do it with a 3X 277/139V bank but not sure) , The 139V is a non-standard voltage and is not used by anything but still brought to the service disconnect and ends there.
Mfrs have caught on and have a variety of these drive isolation transformers 480D:480/277, 240D:240/139, but pump sites have limited space, so often while more expensive up front its worth looking at converting on the utility side. Here the customer (water district) foots the large bill for that and the utility gladly obliges.

 

[zbang]

Was typically for pumping of water, sewage and oil/gas. For new service corner ground is not recommended the why is because of wye;
With the world now all moving to Variable Frequency Drive (VFD) technology, even on old pumps, the VFD's require, or specify a wye configuration dont ask me why, I honestly do not know and found the whole requirement silly at first.

That question has been answered many times in there forums - the requirement is almost always rooted in voltage-to-ground, and that's often because of MOV surge protectors wired from line to EGC. Some drive mfg's provide instructions on how to remove or reconnect those MOVs.