Forum Discussion

bsmith95610's avatar
bsmith95610
Explorer
May 31, 2016

Power Inverter Issues

Hello,

I just bought my first travel trailer a couple of weeks ago and it’s the first camper I’ve ever owned. The trailer is currently wired up to a power inverter that is not currently working. I went ahead and ordered a new 1000 watt power inverter and when I plugged in this power inverter it worked for about a minute then it’s light turned red and the mechanics light that I had plugged into it shut off. If I plug the travel trailer into the house the power inverter works just fine. I’m assuming the deep cycle batteries that are wired in parallel may be the issue but I was wondering how I could test that theory out further. I charged each battery overnight on a trickle charge about a week ago. I touched the leads of the wires with my multimeter and they were at around 11.5 volts and the gauge of wire looks pretty thick to me so I’m assuming that is not the issue. I didn’t know if there was a good way to test out the deep cycle batteries further without buying two new ones. Any help would be much appreciated.

Thanks
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    How much battery do you have?

    Recommended is over 200 amp hours (C/20 rate) for each 1,000 watts of inverter
    That means a pair of GC-2 or a 4D per thousand watts.

    Group 24 75 AH
    Group 27 95
    group 29 105
    Group 31 130

    I'll bet you have a Group 24
  • sounds like you're talking about the converter, not an inverter.

    the converter charges your battery when plugged into shore power or a generator. it converts 120v AC power to 12v DC power.
    all RV's have converters but few have inverters.

    an inverter allows you to run 120v AC items, from your batteries.
  • bsmith95610 wrote:
    If I plug the travel trailer into the house the power inverter works just fine.
    huh?
  • You have a couple of things you need to do. First, if the batteries are really low, trickle charging overnight won't charge them. At a trickle charge rate, it would probably take 3-5 days. Second, a reading of 11.5 volts is basically a dead battery.

    I would pull them out, put a FULL charge on them and then have them tested by a local auto parts store or stop by Harbor Freight and buy one of their battery load testers for $25.00. They work pretty good for occasional use.

    REMEMBER.....You can't test dead batteries. They have to be fully charged before testing.
  • wanderingbob wrote:
    Inverter or converter ? Most inverters will turn to RED when it is a problem in batteries either volts or amps . Being that the load was only a mechanics lite ???


    Maybe this was a halogen work light? Those range from 200W on up...possibly way up, especially for double-headed ones.
  • Inverter or converter ? Most inverters will turn to RED when it is a problem in batteries either volts or amps . Being that the load was only a mechanics lite ???
  • RoyB's avatar
    RoyB
    Explorer II
    Here if a nifty chart showing the approximate charge status of a battery verses DC VOLTS...



    There is a science to charging deep cycle 12VDC batteries...

    "This is what PROGRESSIVE Dynamics states in their operating manual on how long it takes to charge a battery using the DC VOLTAGEs listed below: "Progressive Dynamics ran this test on the amount of time it took a PD9155 (55-amp) converter/charger set to three different output voltages to recharge a 125 AH (Amp Hour) battery after it was fully discharged to 10.5-volts.

    14.4-VOLTS (Boost Mode) – Returned the battery to 90% of full charge in approximately 3-hours. The battery reached full charge in approximately 11 hours.

    13.6-VOLTS (Normal Mode) – Required 40-hours to return the battery to 90% of full charge and 78-hours to reach full charge.

    13.2-VOLTS (Storage Mode) – Required 60-hours to return the battery to 90% of full charge and 100-hours to reach full charge."

    This is based on having 17-20AMPS DC current available for each battery in your battery bank... NOTE That Progressive Dynamics doesn't even list using DC Charge Voltages around the 12.0VC range as this would take alot more than 100 hours to achieve a 90% or 100% charge state."

    Each battery in your battery bank will want to demand 17-20AMPS DC current when you first hit them with 14.4VDC Charge voltage...

    A trickle charge charrge is only good for topping off batteries...

    Also your 1000WATT POWER INVERTER wants to demand around 85AMPS DC CURRENT if fully loaded. That a pretty good amount of current to pull from a battery... They will only hold up for maybe 5 minutes at most. The POWER INVERTERs also will want to have very large DC CABLES connected to the battery terminals to perform properly

    More to this battery thing that meets the eye haha...

    Roy Ken