Ats and generator question

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nickelec

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So I'm going to look at job a little more in depth tonight a little back round

This is commercial building with about 9-10 ats switches feeding multiple loads off of one generator

They had a generator service company come out to test and diagnose the functionality of the ats switches they found that 2 out of the 10 did not have emergency power while in test mode and the generator running but there are wires ran and terminated to the emergency feed in the switch

After a brief visual inspection it looked like to me the generator may have feed a Mdp and then from the Mdp it was supplying multiple ats switches. My question is .. is that a normal set up for the guys here that do large job with generators. Do you typically feed an Mdp then Branch out or does it come off.the generator into basically a large splice box or.trough or whatever to feed the multiple ats switches

My thoughts were if the generator was feeding this Mdp one of the breakers feeding the individual ats with no emergency power could be bad

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It depends on the types of loads served.

If all loads are 702 (optional standby) loads, then that method is fine.

If the loads are 700 loads mixed with 702 loads, then that is not acceptable since the main CB is the single point of failure
 
Can you go a bit further into that explanation as for as what would be considered 702-700 loads

I think the generator is feeding a bus bar inside of an Mdp which is then feeding individual circuit breakers to each individual ats

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I believe 700.10(B)(5) would allow a single feeder to a distribution point as long as the emergency loads are in separate vertical sections of switchgear or separate individual disconnects.
 
So after going back to the job today she's a little more information bear with me I need a little assistance on this one I'm not very familiar with fire alarm systems
It's a 300 KW generator mounted on the roof coming off the generator is one set of fetus that feeds 1000 amp main distribution that is pretty much empty

Then all the equipment that is related to the fire alarm system the pump, the command station have separate disconnects directly off the generator they're actually mounted on the generator so to me it looks like the fire alarm equipment and the normal emergency backup power or isolated is that a code or a design ?

Another question I have is a 400 amp ATS in the basement that is feeding the fire pump I would say probably 300 to 400 feet away from the generator the Wire size is two sets of 2/0 I believe that this is significantly undersized but I can be wrong I'm going to attach a picture of the name plate of the motor what size wire should be feeding this ats and when you size The eire off of the generator do you size it per the breaker in the ats or the load served by the ats
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And if IAM understanding correctly don't the power conductors feeding the controller need to be incased in concrete?

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