Is he blowing smoke?

Discussion in 'General Electronics Chat' started by bombsitebuick, Oct 19, 2011.

  1. bombsitebuick

    Thread Starter New Member

    Oct 19, 2011
    I'm a retired guy trying to help his dad....

    If you bought a POWER CONVERTER that plugs into a cig. lighter to power "Cell phones, PDA, MP3 player, etc. could the output from it be DC vs AC?

    Copy of email to CUST.SVC:
    My father purchased a Rally 85-Watt Power Converter to use on his boat
    to power his CD/MP3 player/recorder (not using batteries).
    On first-use he plugged it in and it blew the power-supply on his
    player. Running a voltage test using multiple autos it reads 250 Volts not 110 as stated. No fuse was blown.
    Could this possible be a European model?
    The unit has a red sticker with 0911402, also a 7 Q.C. PASSED, which I
    assume was your quality control. The box has ITEM 7424 402-19053.
    it has a 2-year limited Warranty but I will not be returning it but wanted you to know of the defect.
    Is there anyway to convert this unit to output 110 volts?

    Response from TECH Support via Cust. SVC
    The Converter does not produce AC power, it produce 110 to 130 Volts DC so therefore when measuring the output make sure that the Volt Meter is set to DC instead of AC. Now if when set to DC the Voltage Meter still reads 250 Volts please send the unit into us for further review.
    Luis Rivera
    Peripheral Technical Advisor

    Sounds like someone is blowing smoke up my butt, right?
    The box doesn't say DC or AC out but.....HOUSEHOLD 110 POWER
    Just checking before I respond to the "TECH ADVISOR'S" EMAIL.
  2. Wendy


    Mar 24, 2008
    I sounds like a commercial inverter. Most of them are simple circuits, they take 12VDC in and come out with 120VAC. However, they also come out with a square wave. This usually doesn't matter for a lot of electronics, but sometimes it does.

    If it is coming out with 200VAC there could indeed be something wrong. A simple test is a drop light with a 60W bulb. Is it the same brightness? If you measure the current what does it draw? It should be around 5A-7A on the DC side, and ½A on the AC side.

    The customer service tech is also offering good advice. You need to measure the AC with a load (such as the light bulb) attached. Light bulbs are cheaper than electronics.
  3. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
  4. BJT_user


    Oct 9, 2011
    Okay I need to roll up my pants legs before I wade into this one. It sounds to me like the tech support person really doesn't know what he's saying. A 12v inverter takes 12 volts DC and converts it to 120 volts AC. There is NO DC involved in the output.
    As for the 250 volts reading on the output, I think they did indeed ship you a model that is set up for European voltage standard, or there is a small option switch somewhere on the unit that switches from 120 to 240. If there is no switch that the user can change, then I would indeed say they owe you a new unit, and the price of whatever device it blew up.