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Power bank blowing fuses?

Lisa Miles
Hi all


I have a question I hope some of you might know the answer to.


We've recently moved over from a builders electricity supply to a domestic supply on our new build house in France. The electrics have all been checked out and signed off by the Consuel.


I have a two port USB powerbank manufactured by a well known battery manufacturer (?) and I was trying to charge it up while I was there using a native two pin USB charger plug. It basically fried the charger plug but didn't trip the fuse on the main board... 


I then plugged it in to a four socket extension lead (two pin plug to three pin sockets) using a three pin charger plug I have. It blew the extension lead but again didn't trip the fuse on the main board. 


At first I thought it must be a fault with the powerbank but  when I got back to the UK, I plugged it into my usual charger and it charged up as normal... ??


What do you think the problem could be? 

Parents
  • 0
    USB power is not a standard in quite the way that say the 13A socket is.

    There is broad agreement that there should be 5V between the outer pins, but how much current you are allowed to draw, and how a voltage source should behave if a load tries to take more current than expected, is distinctly variable.

    The original spec required loads to not draw more than 50mA or connect more than 10uF of flat capacitance until some negotiation has taken place with the host and the load.

    Clearly a dumb power supply cannot negotiate anything, so this spec was widely ignored. Equally a well behaved source should remove its 5V if it detects an overload. This also does not happen, many simpler designs will keep trying to give more current to the point of destruction.

    More recently a simple negotiation has been more or less agreed for charging without a full blown data connection by using resistors to park the data lines from the charger at pre-agreed levels to tell the load how much it should limit its current to.

    I suspect your power pack is expecting a different current limit protocol to that in the chargers.


    info on those current limit standards.       and the 'official' standard, different again.

Reply
  • 0
    USB power is not a standard in quite the way that say the 13A socket is.

    There is broad agreement that there should be 5V between the outer pins, but how much current you are allowed to draw, and how a voltage source should behave if a load tries to take more current than expected, is distinctly variable.

    The original spec required loads to not draw more than 50mA or connect more than 10uF of flat capacitance until some negotiation has taken place with the host and the load.

    Clearly a dumb power supply cannot negotiate anything, so this spec was widely ignored. Equally a well behaved source should remove its 5V if it detects an overload. This also does not happen, many simpler designs will keep trying to give more current to the point of destruction.

    More recently a simple negotiation has been more or less agreed for charging without a full blown data connection by using resistors to park the data lines from the charger at pre-agreed levels to tell the load how much it should limit its current to.

    I suspect your power pack is expecting a different current limit protocol to that in the chargers.


    info on those current limit standards.       and the 'official' standard, different again.

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