2 Replies Latest reply on Jul 8, 2014 11:58 AM by noor

    Need to understand power use for 1238P at different Loads

    fluidnets New Member

      Hi,

       

      I have a 1238P latest GEN Switch with 48 POE Phs connected to it. Ea PH uses about 6W. I see the 1238P is rated @ 500 Watts and 4.9Amps. Would it b safe to say that in the config here, the WATTs being used to determine a UPS run time is 6W x 48 PHs = 288 watts OR is it closer to the 500Watts due to some other factors?

      Same Q for 1534P - I have a 1534P latest GEN Switch with 24 POE Phs connected to it. Ea PH uses about 6W. I see the 1238P is rated @ 500 Watts and 4.9Amps. Would it b safe to say that in the config here, the WATTs being used to determine a UPS run time is 6W x 24 PHs = 144 watts OR is it closer to the 500Watts due to some other factors?

       

      Thanks

      Jim

        • Re: Need to understand power use for 1238P at different Loads
          jayh Hall_of_Fame

          Nameplate power ratings on gear are typically a worst-case maximum.  If all PoE devices are at max and the fans are at max, high CPU, etc. you might come close to the 500 watts.  A clamp-on ammeter with a sense loop (multiply amps times 120 for US) or inline wattmeter such as a Kill-A-Watt will tell you the consumption right now but not the maximum under different conditions.

           

          Nameplate ratings on UPSes are often an optimistic marketer's best hope.

           

          Get a UPS that is capable of 500 watts for safety, your switch should never pull more than that.  Note that run time on the UPS is a function of battery capacity and load, not maximum rating.

          • Re: Need to understand power use for 1238P at different Loads
            Employee

            fluidnets -

            I went ahead and flagged the "Correct Answer" on this post to make it more visible and help other members of the community find solutions more easily. If you don't feel like the answer I marked was correct, feel free to come back to this post to unmark it and select another in its place with the applicable buttons.  If you have any additional information on this that others may benefit from, please come back to this post to provide an update.  If you still need assistance, we would be more than happy to continue working with you on this - just let us know in a reply.

             

            Thanks,

            Noor