Tender wire spark

Posted by George40 On 2018/7/16 21:27:07

I am grappling with an electrical question - The metal nipple on the tender wire coming from my positive ground battery managed to touch the metal door sill, creating a spark and a hot wire. This is something I had never seen from a negative ground battery. When the battery is connected all the way to the tender, there is no problem and it charges well. I called the manufacturer but they just told me to keep the rubber cap on when the tender is not being used so that the metal in the wire would not touch another metal part but did not suggest anything else. Is there any other way to correct this or is it just due to the polarity of the positive ground battery?