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Oasisbob's avatar
Oasisbob
Explorer
Feb 18, 2014

BATTERY CHARGER MYSTER & ?

This morning I decided to perform a maintenance charge on my twin group 27 deep cycle batteries which are isolated from everything via cut off switch. I first hooked up red (positive) charger clip to positive battery terminal then as I began to hook up negative charger cclip to negative battery terminal I noticed an arc. Very odd I thought as I had not yet plugged in charger. So I took off positive and put on negative first. I, again, noticed an arc when I put on positive clip last. The charger is a Chicago Electronics (Harbor Freight) unit which does 6 or 12 volt batteries with amp selections of 2, 10 and 55 for jump starting cars. I had set charger for 2 amp charge. The second I plugged in charger my cord leading to battery clips began to desinigrate before my eyes. Went up in smoke. I,within 5 seconds pulled AC power cord out of the wall then removed battery clips. All insulation on negative cable was gone burning my hand. I put a volt meter on battery and got 12.45. While ripping off battery cables I noted correct polarity. I am baffled as to what happened. There is a reverse polarity indicator on charger which never lit. Any thoughts on what went wrong here? It really concerns me There is no model number on this unit only mfg, date of 2/05 and serial # plate.
  • Thank you all for your thoughts. Makes me leary of leaving any charger unattended though that is not realistic. I am now shopping for a new charger. I found no specific recall info on this charger though the newer models brag about several safety features not found on mine. I had no idea such fire potential existed within that charger.
  • Bob,

    Summary: The charger is toast.

    By your description, your Hazard Fright charger is a version that is called "a simple charger". This means that the box contains only a transformer, rectifier and switches. Well, when one of the rectifiers goes "solid" that is what happens. This could easily have happened the last time you disconnected it.

    It can be repaired for only about twice the cost of a new replacement. Or, you could shop around and get new one that won't boil batteries.

    Matt
  • smkettner wrote:
    Now put the leads on backward and see how it does ;)
    Worst case get a new charger.


    Not likely. He fried the cables, and who knows what else, already.
  • Hi,

    Since you have a meter--put it on a high range and check the out put of the charger.
  • Now put the leads on backward and see how it does ;)
    Worst case get a new charger.
  • Probably would have noticed a problem if you had plugged charger in to outlet before hooking up to battery.

    That charger is toast and was before you used it.
  • Th battery leads on the charger were reversed phase, either externally or internally would be my guess.
  • You get what you pay for. I would never buy anything electrical from them. I would say something went wrong with the charger. Toss it.
  • I have used this charger for maybe 4 years. No problems aside from the amp guage not working since day one. I notice Harbor Freight has a newer similar unit with many safety features mine did not have. How would I see if there was ever a recall or issue with this nit?
  • Since you checked the polarity on the batteries with a meter, I'd suspect the problem was with the charger. I've actually seen a charger (from a certain country that sells junk tires) that had the leads wired wrong inside the unit. In other words, the red lead was negative, and the black lead was positive. Have you ever used this charger before?

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