Question

There is a dangerous design flaw in the DieHard Portable Power 1150. I have called six different numbers at Sears, including Customer Service, without finding anyone who could discuss the danger or tell me who I should call to discuss it. When the user energizes the USB charging port, they also energize the battery clamps. If I am charging a cell phone and someone touches the clamps, they could be severely injured. The USB port and the clamps should be controlled by separate switches. I should also have been able to discuss my concern with a knowledgeable person long before this.

I am a professional chemist and a physics teacher. I hope this is dealt with before someone is hurt. Out of frustration, I have filed a report with the Consumer Product Safety Commission.

Answers

8 answers

  1. As an electrical engineer with over 40 yrs of experience, I will tell you that your specific concern with someone touching the battery clamps accidentally or deliberately will NOT hurt him. The 12VDC is much too low to flow harmful current through any human.
    This portable power pack is designed more than adequately safety-wise.

  2. Thank you physicsandchem for your concern with the portable power units design.

    I have forwarded your concern to the home office saftey division for there review.

    Thank you again for noticing this issue and taking the time to let us know.

    Sam A.

    1. In response to SHC-SamA

      Pls consult your designers about this non-issue. I'm sure they will agree with me that there is no problem.

  3. Have you measured the voltage at the battery clamps? To get a 12 volt battery to 'charge' usually requires about 14 volts which is not enough to hurt a normal healthy person, however a good conductor placed between the two clamps would give a 'short circuit' which could cause excessive heat with possible, and likely burning, and also damage the battery in the unit.

        • San Jose, CA

      In response to inquisitivemind

      I'm amazed the same people who could be touching big'ol battery clamps are around "open" and accessible 120 volt outlets in homes and businesses, everywhere.

      Someone could stick a flat-tipped screwdriver or straightened paper-clip in there and ZAP!

      There should be DANGER - 120 volt warning decals placed on ALL of the outlets and those terminal strips, too.

    1. In response to inquisitivemind

      Practically speaking, there cannot be Danger signs placed everywhere that accidents can occur; imagine "Danger" signs at each of your dozens of home outlets---NO!

      • San Jose, CA

    What is the long model number of the item?

    The first three digits are the OEM code of the company that actually makes the Portable Power device.

    That is 12 volts available on the battery clamps, correct?

    1. Battery voltage is a nominal 12VDC, measuring about (2.2v)/(cell)x(6 Pb cells)=13.2VDC theorectically [Mr. Chemist / Physics Teacher should tell you the same about Pb/PbO2-H2SO4 batteries]. In reality, a fully-charged 12V lead-acid battery will measure about 13.8VDC, and about 14-14.5VDC while charging.

      Hope this all removes the unnecessary concern about the this portable power pack's design. [I had a part-time job for a year with Sears in high school, but am not associated with them in any fashion now, so have no ax to grind either way.]