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Kevin
Kevin, Licensed Electrician
Category: Electrical
Satisfied Customers: 2931
Experience:  29 years as a Licensed Electrical Contractor in Illinois, 5 year college Electrical Instructor, Former Electrical Inspector, Diploma in Digital Electronics, Former Illinois Licensed Home Inspector
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I am at a site where they are mixing 4 20 amp UPS circuits

Customer Question

I am at a site where they are mixing 4 20 amp UPS circuits and 4 20 amp filtered circuits in one 2 inch pvc conduit. All have there own neutral and ground. It gets better. They are all the same phase. I am not interested in conduit fill, I am worried about harmonics and magnetic fields.
Submitted: 4 months ago.
Category: Electrical
Expert:  Kevin replied 4 months ago.

Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.

1) In my opinion and as a former electrical inspector, a poor design by the project engineer or responsible party.

2) Since all circuits reside on the same phase and if the phase is lost for whatever reason, so much for putting all the eggs in one basket. Poor design decision. Circuits should have been spread out on other phases in order to minimize any potential losses if loosing one power phase.

3) Yes, I agree with you regarding potential problems caused by harmonics and/or EMI.

4) Personally, I would have installed the different circuits using separate raceways (UPS and branch circuit raceways) to minimize and/or reduce any potential harmonics or capacitive and/or inductance issues. A local electrical inspector may consider and by code interpretation that the UPS circuits are emergency circuits or control circuits and should not be inter-mixed with branch circuits within the same raceway. Local electrical codes always have the final say so. I recommend to run this past the local electrical inspector.

5) Conduit fill ratio also needs to be taken into consideration as well as conductor deratings due to the quantity of conductors in the raceway.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks.............Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks..............Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks..............Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks.................Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks.................Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks.................Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks.................Kevin:)

Expert:  Kevin replied 4 months ago.

If you have any additional questions, just let me know and I’ll be glad to answer them for you.

Otherwise, don’t forget to rate me before you log Off.

Thanks..................Kevin:)

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