Forum Discussion

BFL13's avatar
BFL13
Explorer II
Mar 15, 2021

TV on Inverter 2000w VS 300w Draws

Tested for this with each inverter clamped to battery bank in turn, 32" TV, and Trimetric for volts and amps.

300w- off: 12.6v, 00.2a
on: 12.6v, 00.5a
TV on: 12.5v , 9.2a (climbing slowly with "inverter creep")

2000w- off: 12.6v, 00.2a
on: 12.6v, 00.9a
TV on: 12.5v, 9.3a (climbing slowly with "inverter creep")

300w in 12v socket in "TV panel" alarmed off- (wires too thin)

Note in previous threads about this, it came out that the loaded amps depends on the load's place on the efficiency curve of each inverter and you can't just add the load to the standby draw.

Each inverter has its own 12v wire gauges. I did not test for using fat wires with the 300w, just the ones it came with.
  • theoldwizard1's avatar
    theoldwizard1
    Explorer II
    Mar 16, 2021
    Hurricaner wrote:
    The msw inverters will generally be more efficient on some loads as there is just a lot less components.

    Generally true. However, most MSW inverters use older designs. Modern PSW, especially those designed in the past 10 years, have the advantage of much more efficient MOSFET power transistors.
  • BFL13's avatar
    BFL13
    Explorer II
    Mar 16, 2021
    theoldwizard1 wrote:
    Bigger inverters typically require more power for themselves.


    The OP is an attempt to measure how much to see whether it is enough to matter.
  • BFL13's avatar
    BFL13
    Explorer II
    Mar 15, 2021
    Hurricaner wrote:
    The msw inverters will generally be more efficient on some loads as there is just a lot less components. To get an apple to apple comparison both inverters should be of the same type. I would also rerun the test with a 100 watt light bulb. Tvs can draw different currents depending on the picture being displayed.

    Sam


    Yes, TV draw depends on the picture brightness selected--the brighter the higher the draw. In the OP test, the TV stayed the same.

    If the MSW would be more efficient, that just makes the PSW 2000w inverter in the OP look better I think.

    I do have a 3000w MSW in the attic somewhere I could try. It has a display panel though, showing watts draw and battery volts, so that would add a little to the "on" draw I suppose. Might get at that later
  • Hurricaner's avatar
    Hurricaner
    Explorer
    Mar 15, 2021
    The msw inverters will generally be more efficient on some loads as there is just a lot less components. To get an apple to apple comparison both inverters should be of the same type. I would also rerun the test with a 100 watt light bulb. Tvs can draw different currents depending on the picture being displayed.

    Sam
  • time2roll's avatar
    time2roll
    Nomad
    Mar 15, 2021
    OK yes. So really 300 and 700 mA respectively. That is reasonable.

    I agree once under a small load it is all about the same. My old Xantrex 1800 pulled a solid 2 amps at idle. That seemed to add up quick when left on overnight (doing nothing) and then recharging at the dreaded WFCO 13.6 volts.
  • BFL13's avatar
    BFL13
    Explorer II
    Mar 15, 2021
    The "off" amps was what showed on the Trimetric before turning it on, due to whatever draw was already on in the RV --LP alarm etc. I have no measurement for the just the inverter when off ( I doubt there is any, but PT mentioned loading of capacitors and sparking when you connect to battery--but then would it not just sit like that?)
  • time2roll's avatar
    time2roll
    Nomad
    Mar 15, 2021
    200 milliamps when turned off??? My 300w GP has an idle draw spec of 200 mA. I would think off was a bit less.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Mar 15, 2021
    So there is little if any "savings" by using a smaller inverter when the TV is in use. Thank you.
  • BFL13's avatar
    BFL13
    Explorer II
    Mar 15, 2021
    2000w is PSW and 300 is MSW--does it matter with a TV? I know the microwave draws fewer amps with MSW.

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