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E stop NEC 2014 Article 514

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    E stop NEC 2014 Article 514

    Attached sketch shows gas station convience store inside has Panel C, their is also Panel schedule C, outside store 5 dispensers, outside store 3 E stops and power riser Panel C with three E stops and feeder from feeder breaker from another panel feeding Panel C.

    Sketch shows that their is 20A feeder breaker from Panel C schedule circuit #20 going to power three E stops. The feeder cable size is 2# 14.

    120/208V three phase Panel C feeds gas station Dispensers, tank STP pumps, Air comp, price sign.

    I really need help in regards to those of you who have actually wired or have knowledge gas station E stop following question:

    1. Can their be a feeder breaker from dispenser/pump panel to feed the E stop for power? If yes then what is E stop powering its just a contact switch no?

    2. If yes to #1 then does it need equipment grounding conductor? If no to #1 then what powers the E stop?

    3. Power riser shows one feeder to E stops in series. I thought the E stop is suppose to disconnect dispenser all power, data communication, video NEC 2014 Article 514.11. Should not E stops be on and disconnect feeder to Panel C or all Dispenser feeder?

    4. Note Panel C also feeds tank STP pumps, Air comp, price sign. Do those need to be disconnect by E stop?

    5. I thiught E stop had control circuit. What is the purpose of 2#14 if not power?

    Thank you for your input

    Sent from my SM-G935U using Tapatalk

    #2
    While I did not look at your sketch, I can tell that to met the requirments this is typicaly done with a listed control box that is made for this purpose. It is really the only practical way to comply with the code when you consider all the types of circuits/conductors that are typically used in a modern retail fuel outlet. All the petroleum equipment makers have this stuff available.

    Comment


      #3
      Originally posted by texie View Post
      While I did not look at your sketch, I can tell that to met the requirments this is typicaly done with a listed control box that is made for this purpose. It is really the only practical way to comply with the code when you consider all the types of circuits/conductors that are typically used in a modern retail fuel outlet. All the petroleum equipment makers have this stuff available.
      Dont follow what you are saying. Attached sketch post#1:

      1. Can their be a feeder breaker from dispenser/pump panel to feed the E stop for power? If yes then what is E stop powering its just a contact switch no?

      2. If yes to #1 then does it need equipment grounding conductor? If no to #1 then what powers the E stop?

      3. Power riser shows one feeder to E stops in series. I thought the E stop is suppose to disconnect dispenser all power, data communication, video NEC 2014 Article 514.11. Should not E stops be on and disconnect feeder to Panel C or all Dispenser feeder?

      4. Note Panel C also feeds tank STP pumps, Air comp, price sign. Do those need to be disconnect by E stop?

      5. I thought E stop had control circuit. What is the purpose of 2#14 if not power?

      Sent from my SM-G935U using Tapatalk

      Comment


        #4
        Originally posted by hhsting View Post
        Dont follow what you are saying. Attached sketch post#1:

        1. Can their be a feeder breaker from dispenser/pump panel to feed the E stop for power? If yes then what is E stop powering its just a contact switch no?

        2. If yes to #1 then does it need equipment grounding conductor? If no to #1 then what powers the E stop?

        3. Power riser shows one feeder to E stops in series. I thought the E stop is suppose to disconnect dispenser all power, data communication, video NEC 2014 Article 514.11. Should not E stops be on and disconnect feeder to Panel C or all Dispenser feeder?

        4. Note Panel C also feeds tank STP pumps, Air comp, price sign. Do those need to be disconnect by E stop?

        5. I thought E stop had control circuit. What is the purpose of 2#14 if not power?

        Sent from my SM-G935U using Tapatalk
        Can someone please help in regarding post #1?

        Sent from my SM-G935U using Tapatalk

        Comment


          #5
          Originally posted by texie View Post
          While I did not look at your sketch, I can tell that to met the requirments this is typicaly done with a listed control box that is made for this purpose. It is really the only practical way to comply with the code when you consider all the types of circuits/conductors that are typically used in a modern retail fuel outlet. All the petroleum equipment makers have this stuff available.
          I agree, most cases are going to use a control panel that already has things needed built into it, all you do is run incoming/outgoing power leads a switch loop for E-stop(s) and with most modern ones probably a communications cable for the attendant's console/or other interface with the point of sale equipment.

          Originally posted by hhsting View Post
          Dont follow what you are saying. Attached sketch post#1:

          1. Can their be a feeder breaker from dispenser/pump panel to feed the E stop for power? If yes then what is E stop powering its just a contact switch no?
          The E stop switch itself is just a single pole (maybe set of 1 NO and 1 NC and use what you need for your application) dry contact. Is probably a general purpose "E stop switch" and you connect it according to your needs.

          2. If yes to #1 then does it need equipment grounding conductor? If no to #1 then what powers the E stop?

          EGC might not be needed if the control circuit is a class 2 control circuit. With modern control systems this E stop is nothing more than a switch loop from the control system - power and what is controlled by it are covered in the system all you are doing is adding a necessary external component.

          3. Power riser shows one feeder to E stops in series. I thought the E stop is suppose to disconnect dispenser all power, data communication, video NEC 2014 Article 514.11. Should not E stops be on and disconnect feeder to Panel C or all Dispenser feeder?

          If you have some sort of made in the field setup - which even if electrical inspector approves the fire officials may not, you might possibly be able to set this up to put shunt trip breaker on a "fuel panel" or a main contactor supplying a fuel panel and use this E stop to control power to the control panel.

          4. Note Panel C also feeds tank STP pumps, Air comp, price sign. Do those need to be disconnect by E stop?

          5. I thought E stop had control circuit. What is the purpose of 2#14 if not power? It is a simple switch loop that is a sub part of the wiring system. If it originates from an individual breaker it could easily be switch in series with supply power to the rest of the controls.

          Sent from my SM-G935U using Tapatalk
          I live for today, I'm just a day behind.

          Comment


            #6
            I do not understand what the E-stop system consist of. I think that is also your problem, you do not understand what is being asked for.

            I used to use a contactor(with an auxiliary contact for the E-stop) that also broke the neutral to feed a fuel panel. I wired the E-stops in series like the stop button of a start/stop system. The start button would be adjacent to the contactor (or mounted in the cover) or fuel panel. You would have to get your E-stop circuit out of the panel feeding the contactor or use an OCP device and get it off the line side of the contactor.

            Comment


              #7
              While I highly recommend it, a listed control panel is not currently nor an anticipated requirement in the future. For most hazardous location issues, the NEC does not require anticipating dual concurrent failures.
              "Bob"
              Robert B. Alexander, P.E.
              Answers based on 2017 NEC unless otherwise noted.

              Comment

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