Anyone checked the current draw of their inverter microwave at a given power setting? Does a power setting of, say 50%, also drop the current draw approx. 50%? Thanks!

Interesting question..I am looking at a new MW for our TT and the inverter MWs sure are tempting, the one we looked at was rated 1250W output but only required 1400W input.. The reason we are are considering an inverter MW is getting more than 1100W output but using the same power as a 1100W non inverter MW.I suspect though if you set an inverter MW for 50% it will more than likely PWM modulate the on vs off time like regular non inverter MWs averaging over all lower wattage but with high wattage spikes when on.But would be interesting to see if anyone that has an Inverter MW sees anything different than my guess..

Just did a test on my inverter mic and at full power it draws 16 amps. At 50% power it draws 8 amps. Tested with a Kill A WATT meter.

One of the guys here posted about his Panasonic MW that pulls less power with lower settings. A "normal" MW draws full power when on, but at lower settings is not "on" as much.A MSW inverter will draw less from the battery bank than a PSW inverter with a MW as load, but it takes longer to "cook" something. Even so, I found the MSW draws fewer AH doing that because the Amps component is bigger than the Hours component. Also a potato is "ready" when you stick a knife in it, and how soft you want it is subjective, and it softens more after you take it out of the MW, so just when is a potato "done" anyway?Also with things you have to cool down before you can eat them. Why get them so hot? Some older MWs like the one in our 1991 C will not run on MSW so you need a PSW inverter anyway. MWs since at least 2003 (as in our 5er we had) run ok on MSW. You do need a MSW inverter that is rated to run motors though. They can do a MW.

BFL13 wrote:One of the guys here posted about his Panasonic MW that pulls less power with lower settings. A "normal" MW draws full power when on, but at lower settings is not "on" as much.A MSW inverter will draw less from the battery bank than a PSW inverter with a MW as load, but it takes longer to "cook" something. Even so, I found the MSW draws fewer AH doing that because the Amps component is bigger than the Hours component. Also a potato is "ready" when you stick a knife in it, and how soft you want it is subjective, and it softens more after you take it out of the MW, so just when is a potato "done" anyway?Also with things you have to cool down before you can eat them. Why get them so hot? Some older MWs like the one in our 1991 C will not run on MSW so you need a PSW inverter anyway. MWs since at least 2003 (as in our 5er we had) run ok on MSW. You do need a MSW inverter that is rated to run motors though. They can do a MW.Standard MWs use a PWM method when you set the power level lower than 100% basically changing the duty cycle to control power level. Basically the average power is lower during the MW operation.They vary the time ON vs Time OFF and when ON, the magnetron is at full wattage.Example, 90% power level and the magnetron is ON 90% of the time and 10% OFF of the time.50% setting magnetron is ON 50% and OFF 50%.Boondocker has said that they see half the current draw at 50% with their Inverter MW which means the inverter type are not using full on power, so they must be lowering the magntrons input voltage to lower the output.Interesting..

Gdetrailer wrote:BFL13 wrote:One of the guys here posted about his Panasonic MW that pulls less power with lower settings. A "normal" MW draws full power when on, but at lower settings is not "on" as much.A MSW inverter will draw less from the battery bank than a PSW inverter with a MW as load, but it takes longer to "cook" something. Even so, I found the MSW draws fewer AH doing that because the Amps component is bigger than the Hours component. Also a potato is "ready" when you stick a knife in it, and how soft you want it is subjective, and it softens more after you take it out of the MW, so just when is a potato "done" anyway?Also with things you have to cool down before you can eat them. Why get them so hot? Some older MWs like the one in our 1991 C will not run on MSW so you need a PSW inverter anyway. MWs since at least 2003 (as in our 5er we had) run ok on MSW. You do need a MSW inverter that is rated to run motors though. They can do a MW.Standard MWs use a PWM method when you set the power level lower than 100% basically changing the duty cycle to control power level. Basically the average power is lower during the MW operation.They vary the time ON vs Time OFF and when ON, the magnetron is at full wattage.Example, 90% power level and the magnetron is ON 90% of the time and 10% OFF of the time.50% setting magnetron is ON 50% and OFF 50%.Boondocker has said that they see half the current draw at 50% with their Inverter MW which means the inverter type are not using full on power, so they must be lowering the magntrons input voltage to lower the output.Interesting..From what I understand this is the way it operates.

Inverter Microwave - Current Draw vs. Power Setting

ktmrfs
Explorer II
Jul 02, 2021
I did a test with a killowatt meter years ago when I installed a panasonic true inverter mw. Besides doing a MUCH better job of cooking at lower power, yes, current draw is reasonably linear with power setting. On mine 50% power draws 800VA, just perfect to run from my 1000VA true sine inverter. draw keeps dropping all the way to 10% and I didn't see any cycling jumps in power below 30% as others have mentioned, but at the low power level, the constant draw from the rest of the electronics comes into play and at 10% power IIRC it still drew aroun 25% of full rated power.
MEXICOWANDERER
Explorer
Jul 04, 2021
There should be a plateau minimum somewhere down in the power range. Just like a stereo with the volume turned off. My 1875 watt commercial microwave (20 amp plug) draws a disproportionate amount of energy and it's not modulated it's simply timer variable on-off. I laughingly refer to it as "555 control"

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