[sdunlimited]

Hello,

I am not electrically inclined and am trying to assist someone with an issue.

They're trying to run a 480V device off a 150KW generator using 400' of commercial extension cords.
The first cord is hard wired in the generator and has a 4 prong plug rated at 480V. The device will run when plugged directly in to this cord.
The other extension cords and ends say they're rated for 250V. Will this impact the voltage going to the device?

The device will not turn on or run when plugged in at the end of this length of cords.

My guess is that's it's due to the rating of these cords but I would like to confirm if possible.

Thank you for any and all guidance or advice.

 

[mm11]

Hire an electrician.

 

[Oso954]

480V is not a DIY project.
The best advice to you is back away from the project.
The best advice to the "someone" is to hire an electrician before he damages his device, or someone is killed/injured.

 

[sdunlimited]

The issue at hand isn't necessarily the voltage, but determining if there's a problem with the connection. The generator functions fine, the device (pump) functions fine, but the connections seem to have a failure point somewhere.

As I was typing this, the people who provided the cables told the guys on the ground that they gave them the "wrong plugs". I saw pictures of them, 480V 50A center ground off the generator and 4 prong, 250V 30A for the rest. As my initial question asked, it appears that is the issue. I don't know enough about it to say why, but figured it was limiting the electricity reaching the device hence why it wouldn't run. New cables are enroute and will hopefully sort the issue.

 

[joed]

The rating on the plugs will not prevent the device from operating. They just might not be able to handle the load and burn up. Something else is wrong.
This is not a DIY project. Call an electrician.

 

[Daniel Holzman]

I am not certain why you would allow yourself to be involved in this project, given that by your own statement you know little about electrical connections. As others have noted, connecting a 480V device is dangerous and potentially fatal, you have nothing to add to the discussion, and no one on this forum should be offering any advice to you other than to step back and recommend that the person running the project hire a qualified electrician.

 

[sdunlimited]

I am 3,000 miles away from the project trying to source information for the person on the ground who was looking for assistance.

The problem has been resolved. Again, as mentioned at the outset, it's not related to the voltage of the generator or device. My initial question was regarding the different rated cables and the potential impact they could have on delivering electricity to the device.
After determining that there should be negligible drop in voltage over 400' of cable, it must be an issue with the connections. Sure enough, one cable had a severed lead and several others apparently had polarities crossed. These have been remedied and all is right with the world again. With no fatalities to boot...

 

[AllanJ]

The cable rated for 250 volts will carry current of a 480 volt circuit end to end but could short out in the middle.

When the cable is rated for 250 volts, that means that voltages 250 volts and below will not jump between internal metal parts or jump right through the insulation of wiring from one wire to another. If current makes the jump, the resulting arc will melt or burn anything nearby.