Forum Discussion

drcarr57's avatar
drcarr57
Explorer
Oct 09, 2013

Inverter

The voltage shown inside the coach useing a plug in meter shows 130+ volts. This does not seem normal.Is there a regulator on the inverter, that may be going bad? The inverter is a Xantex Freedom 458.
  • drcarr57 wrote:
    The voltage shown inside the coach useing a plug in meter shows 130+ volts. This does not seem normal.Is there a regulator on the inverter, that may be going bad? The inverter is a Xantex Freedom 458.


    the inverter has no controll over the voltage being induced via shorepower if your talking shore power.If your saying that when on invertion(non shore) power it shows 130V then I would be checking your meter accuracy first and then go from there
  • FOUND THIS ARTICLE:
    Actually, there may be nothing wroing with your inverter. 150 volts sounds about right for that unit. The Freedom 458 is a modified sine wave inverter. Modified sine waves are not true sine waves, they are squared off. Voltage is actually measured at RMS levels on a true sine wave, which will peak at 170 volts but only for an instant and then return to baseline. The RMS voltage will read 120, which is what you want. But a modified sine wave is square. It shoots straight up to 150 volts, stays there for a while, and then falls to the baseline. For a better explanation on this check out the article in the RV Tech Library at http://www.rvtechlib...al/sinewave.htm for more details.
  • My plugin volt meter displays over 140 VAC when on just the inverter, but shows 120+/- VAC on shore power and generator. Possibly a MSW issue.
  • 130 is at the very high end of normal. What is the voltage with 100+ watt load?
    Most charging bricks are good for 100 to 250 volts.
  • Mr. Prism explained it well, what you are seeing is normal for a MSW inverter.
  • First thing you need to do is get a "True RMS" volt meter when measuring inverter outputs. True RMS can be very different then what simple meters think is correct.... :)
  • tomousecap wrote:
    First thing you need to do is get a "True RMS" volt meter when measuring inverter outputs. True RMS can be very different then what simple meters think is correct.... :)
    X2

    I use THIS plug in voltage tester I picked up at camping world. It tests and reads RMS ... MSW Inverter voltage. It also reads shorepower, so it's all I need and it's always plugged in so all I need to do is glance at it.

    Take out the guesswork and you'll get accurate results. :)
  • I thought MSW tended to read low with a peak voltmeter. (vs true RMS)