20160606
Hi all,
I'm often in situations where I have only 15 amps to play with.
I am adverse to running the roof air when voltage drops below 108.
I do not yet own an autoformer.
The Magnum offers load support, but not voltage support.
The test:
to run roof air on 1/2 from a 50 amp outlet with 70 feet of #10 extension cord (one plug at 30 feet, and one at the RV). Load support enabled. Input current limited to 30 amps.
The results with voltage measurement inside RV.
Line voltage only the fridge as a load 109. watts 335 0 load support amps
Line voltage with air conditioner and fridge on 105.3 watts 1695; 17 load support amps.
Line voltage with only air conditioner 107.3 watts 1437.
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running on inverter only--no shore power
voltage only the fridge as a load 117.7 320 watts
voltage with air conditioner and fridge 118.7 1673 watts
voltage with air only 118.7 watts 1385 amps 137
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I then deliberately "dialed down" current input to 5 amps.
line voltage running fridge only 111 volts 320 watts
line voltage running air and fridge 109 1685 watts
line voltage running air only 110.8 1387 watts load support amps 54.
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Conclusion, it is possible to force the Magnum to do voltage support by "dialing down" the input current limit.
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.