400 Rated I-line busway

[Davebones]

Have engineer that wants to install a test stand that has two 150 hp motors on a 400 amp bus . I told him I don't think this is a good idea as nothing else could run if we ran this stand . Would any of you even consider doing this on a 400 amp bus ????

 

[petersonra]

150 HP = 180 A FLC

180*1.25 + 180 = 405 A.

I just don't have a huge problem with what is being done. How is this any different than running two sets of conductors to feed the motors seperately? You wouldn't have any spare capacity then either.

Spare capacity is solely a design consideration.

having said that, bus is an expensive way to feed a couple of motors. six 4/0 in a single conduit would likely be a lot less costly.

 

[kwired]

150 HP = 180 A FLC

180*1.25 + 180 = 405 A.

I just don't have a huge problem with what is being done. How is this any different than running two sets of 4/0 to feed the motors seperately? You wouldn't have any spare capacity then either.

Spare capacity is solely a design consideration.

having said that, bus is an expensive way to feed a couple of motors.

What Bob said, plus you say nothing else can run, yet you never mentioned there was something else. Is the two motors the only load or is there more load?

 

[Davebones]

At this point he is saying only 2 motor's . We have some other smaller loads on this bus . I get the ole " We won't run it at full load only once in a great while " . I looking at a 600 amp bus switch just to feed this if we do it .

 

[petersonra]

At this point he is saying only 2 motor's . We have some other smaller loads on this bus . I get the ole " We won't run it at full load only once in a great while " . I looking at a 600 amp bus switch just to feed this if we do it .

Now you have changed your story. If there are other loads, you would probably be well advised not to go with 400A bus.

personally, I am not a huge fan of bus. it is expensive and eats up a lot of room overhead. is the engineer fixated on using bus for some reason? there are cases where it is handy, and other cases where it is not a very good choice.