50A CB for small load at 3 Phse 208V

Isaiah

Senior Member
Location
Baton Rouge
Occupation
Electrical Inspector
I’m still wondering why/how a major engineering firm sized a three phase CB at 50A for 3phase 208V Control panel that is rated just 4800VA. I’m seeing at CB of around 15A is all that’s needed


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Engineer 1: Yea, size the breaker at fifteen
Engineer 2: fifty?
Engineer 1: Yep, fifteen

Could be a classic communication error.
Oh, I can totally see that happening... :D

I had a coworker once who pronounced all "Fs" like the letter "P"... so he would for example say "I need to put in a pipty amp puse", or a "pipteen amp puse". It was frustrating. I figured it out right away simply because my name is Jeff, and he called me "Jepp". So once I was able to decode his speech, he began only talking to me! Oh joy...
 
P, T, E, D, G, C = huh, to me. Fifty, sixty ?? And hollering doesn’t help. Aids do, but look at me, not the fricking wall. You know I can’t hear well!!

Sorry, rant done.
Your rant is well deserved. I don't suffer from hearing loss, my granddad and two brother in laws do. It frustrates me to see how people treat them. You wouldn't expect a person in a wheel chair to run to the top of the stairs to look at something you want to show them, and just say, "Never mind" when they don't get there as fast as someone that can walk. Can't hear well though, and you become the jerk instead of the person who is being the jerk.

When I'm with someone that I know can't hear well I do my best to face them when talking and won't get irritated if they ask me to repeat.
 
Engineer 1: Yea, size the breaker at fifteen
Engineer 2: fifty?
Engineer 1: Yep, fifteen

Could be a classic communication error.
Possible, but its also possible that the engineer just didn't know what the load was going to be.

Owner; "We're adding a control panel. You need to provide power for it."
Engineer; " how much power are we talking about?"
Owner: "I don't know." or "It hasn't been designed yet." or "The vendor will get back to you" or "Take a guess, but I don't want a change order later...", or a multitude of other responses that are no help at all.
 
I’m still wondering why/how a major engineering firm sized a three phase CB at 50A for 3phase 208V Control panel that is rated just 4800VA. I’m seeing at CB of around 15A is all that’s needed


Enviado desde mi iPhone utilizando Tapatalk
Maybe they have a design criteria to not have less than 50 A feeders to such things. Or did not know the exact current required. Or made a mistake. Or there is some future load to be potentially added that is none of your business. Its code compliant. That is all that matters.
 
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