No load current
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Abodyofscience
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Idling, it appears to pull 12w.
Find specs on several other inverters to find out if this value is typical, or larger than average.
Find specs on several other inverters to find out if this value is typical, or larger than average.
RCinFLA
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Be careful on specs. 12 watts running idle on a 1200 watt sinewave inverter sounds a bit too good to be true.
Many Chinese inverters spec standby mode current for no-load current. Standby is periodic strobing ON of inverter to check if there is a load. If no load is detected it turns off for a period of time, then tries again after some sleep time. The low ON duty cycle improves their average current consumption.
Standby mode has two common problems. Lite loads, less than 5 to 10 watts may not wake them up. Second is appliances with microprocessor controllers will do a hard reset when AC power is turned off and inverter ON sense time period may not stay ON long enough for appliance bootup time. So appliance stays off. A lot of simple appliances these days have a cheap microprocessor controlling them.
Many Chinese inverters spec standby mode current for no-load current. Standby is periodic strobing ON of inverter to check if there is a load. If no load is detected it turns off for a period of time, then tries again after some sleep time. The low ON duty cycle improves their average current consumption.
Standby mode has two common problems. Lite loads, less than 5 to 10 watts may not wake them up. Second is appliances with microprocessor controllers will do a hard reset when AC power is turned off and inverter ON sense time period may not stay ON long enough for appliance bootup time. So appliance stays off. A lot of simple appliances these days have a cheap microprocessor controlling them.
Abodyofscience
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Even if they are all lying in the same direction, with a half dozen values we can find the biggest liars.
Then correlate the numbers with Chinese or "other".
This should be good.
Then correlate the numbers with Chinese or "other".
This should be good.
This Epevers seem to be almost double and is giving the 2 values idle and no load
RCinFLA
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20 watts (24vdc x 0.9A) of no-load run power sounds more realistic for 1000w to 1500w sinewave inverter.
The output PWM L-C filter has some reactive currents at no output load that causes greater no-load idle losses.
Dominate no-load power consumption is driving the MOSFET gates at 20-30 KHz chopping and reactive current of L-C output filter.
Since the number of parallel MOSFET's and size of MOSFET gate capacitance goes up as inverter power capability goes up, the higher the inverter wattage rating the more no-load battery current. Some inverters shut off some of the parallel MOSFET's at low power but this has negative side effects for surge loads.
The output PWM L-C filter has some reactive currents at no output load that causes greater no-load idle losses.
Dominate no-load power consumption is driving the MOSFET gates at 20-30 KHz chopping and reactive current of L-C output filter.
Since the number of parallel MOSFET's and size of MOSFET gate capacitance goes up as inverter power capability goes up, the higher the inverter wattage rating the more no-load battery current. Some inverters shut off some of the parallel MOSFET's at low power but this has negative side effects for surge loads.
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What is the difference in the no load idle current for a 2500W, 30khz inverter with, say, 4 of the yellow transformers, and an inverter with only one toroidal transformer, everything else being similar?
RCinFLA
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Idle current on a given inverter is more a case of good or poor design.
Higher switching speeds takes greater switching device gate drive power.
Lower resistance switching devices have greater gate capacitance requiring greater gate drive power.
HF inverters have more power devices to chop at higher frequencies than a LF inverter design.
Higher circuit current capability has greater losses. The greater the inverter wattage capability, the higher the idle current.
Sinewave PWM filtering is a compromise between low load and high load filtering.
Reactive currents from a poorly designed sinewave PWM filter creates switching device losses.
Reactive currents from a skimpy power transformer design creates greater switching device losses.
I would say poor sinewave PWM filter design is the number one cause of high idle power. A lot of poor design practices is driven by keeping component cost low. Number one priority for Chinese inverter designs.
Higher switching speeds takes greater switching device gate drive power.
Lower resistance switching devices have greater gate capacitance requiring greater gate drive power.
HF inverters have more power devices to chop at higher frequencies than a LF inverter design.
Higher circuit current capability has greater losses. The greater the inverter wattage capability, the higher the idle current.
Sinewave PWM filtering is a compromise between low load and high load filtering.
Reactive currents from a poorly designed sinewave PWM filter creates switching device losses.
Reactive currents from a skimpy power transformer design creates greater switching device losses.
I would say poor sinewave PWM filter design is the number one cause of high idle power. A lot of poor design practices is driven by keeping component cost low. Number one priority for Chinese inverter designs.
Rednecktek
Solar Wizard
Just to throw it out there, Will recommends the Giandel inverters so they can't be that bad.
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