Battery system safety shield and method
Storage batteries connected in series in an uninterruptible or back-up power supply system may have voltage potential differences between exposed terminals or conductors that exceed safety limits. A demountable insulating shield having apertures may be positioned so that the series string may be broken into a plurality of series sub-strings having a lesser potential difference has a cover over the aperture through which the series string configuration may be connected and disconnected. The cover may be an insulating material removably fastened to the insulating shield or a sliding cover that is captivated to the insulating shield. When the series string has been divided in to the sub-strings, the insulating shield may be demounted from the structure housing the batteries so that the batteries or their connections may be serviced.
1. A method of servicing a storage battery system, comprising:
providing an non-conductive barrier having an aperture therein and a non-conductive cover sized and dimensioned to prevent access to the aperture when the cover is in a first state;
mounting the non-conductive barrier with respect to a rank of storage batteries such that access to electrically conducting parts having a potential difference therebetween that is greater than a predetermined value through adjacent covers is prevented;
moving the non-conductive cover so as to permit access to the electrically conducting parts through the aperture;
dividing the series string into a sub-string by opening or removing an electrical connection between two storage batteries of the plurality of storage batteries, continuing to perform the steps of moving and dividing until each of the sub-strings has a potential difference with respect to any other electrically conducting parts that is less than the predetermined value; and
removing the non-conductive barrier.
2. The method of claim 1 , wherein the step of moving is sliding a captivated non-conductive cover to expose an aperture.
3. The method of claim 1 , wherein the step of moving is removing the non-conductive cover.
4. The method of claim 1 , wherein the predetermined value is nominally 50 VDC.