3 phase supply, single phase inverter

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • GCE
    Platinum Member

    • Jun 2017
    • 1473

    #16
    Originally posted by Dylboy
    Yes that's how I have it too

    It's nice as the cheap inverters the moment 5kw is on pulled the thing shuts down.

    Also some houses not possible to rewire circuits to take the dishwasher, washing machine off the essential circuits as it powers the internet for example so the pass through is great as then they can still run when there is grid.

    Sent from my CPH2197 using Tapatalk
    We are seeing problems with that logic - If the dishwasher , washing machine etc is running and there is a dip in power then the inverter trips because the essential side is overloaded . It also runs the battery down quickly if the people do not realize that the grid has dropped out.
    It is much safer/a requirement, to ensure that the load can never exceed the essential side output. Clause 7.12.2.4 ( pasted below) requires you to ensure that the capacity is not exceeded.

    Rather use the feedback function ( as put so eloquently by Justloadit further up ) to supply the non essential loads with solar and a set percentage of battery to compliment the grid usage.

    If it is purely back up then ensure that any possible load that could be connected and running is covered by the sizing of your unit.
    Next you will be saying that the client does not want to pay extra to wire extra circuits to the TV, Router , Alarm and limited lights and so you do as he requests with the money he says is available.
    This is why the industry is where it is, as the client that has no electrical knowledge and taking no responsibility when something goes wrong is determining how we as professionals are doing our jobs and take the risks.

    If your doctor says , Hey bud you need a triple bypass , you don't say , Hang on I only have money for one valve to be bypassed and then your wife sues him when he does only one , leaves the other 2 and you drop dead a month later - He just says go elsewhere if you are not taking my professional opinion seriously , it is 3 valves or none. The risk of having a comeback is to high and I am walking away , go find someone else that is prepared to put his practice at risk. You won't find that person because the doctors all stick to doing what is correct, not what financially suits you.

    Why do we do differently ?


    7.12.2.4 Where the alternative supply is intended to provide a supply to an
    installation that is not connected to the main supply, or to provide a supply as
    a switched alternative to the main supply, the capacity and operating
    characteristics of the alternative supply shall be such that danger or damage
    to equipment does not arise after the connection or disconnection of any
    intended load as a result of the deviation of the voltage or frequency from the
    standard range. Means shall be provided to automatically disconnect such
    parts of the installation, as may be necessary if the capacity of the alternative
    supply is exceeded
    .

    Comment

    • Isetech
      Platinum Member

      • Mar 2022
      • 2274

      #17
      Why do we do differently?

      The same reason people are doing COC's for R650 and you can get a socket outlet installed at R450 per point ?
      Comments are my opinion, unless regulations are attached to support the comment. This is social media, not a court room.

      Comment

      Working...