The exact response was "none of the units on that page are LF type".They all have transformers.. I think what you're asking is which are low frequency vs high frequency.
LF inverters have big honking heavy transformers while HF units have small transformers.
As far as I know, none of the units on that page are LF type.
In your refereed website,all of them are high frequency inverters,and use small transformers.
Are we looking at same website?The exact response was "none of the units on that page are LF type".
What on earth do you consider LF inverter?The pictures are deceiving as the units are small. The Victron MultiPlus 3000W unit is 14.3”x10.2”x8.6” and weighs 40 lbs. Data Sheet.
My 2700W UPS weighs around 100 lbs without batteries. Below picture illustrates the size difference with my Reliable 2500W HF inverter.
Edit: the Victron does have larger than usual transformers, however switches at 20khz so cannot be considered 60hz LF. YouTube Video
SMA Sunny Islands are true low frequency inverters.What on earth do you consider LF inverter?
AFAIK its the Frequency ”seen” by output transformer.
So how do the magnum&SMA generate the sine wave?SMA Sunny Islands are true low frequency inverters.
They are only a single phase 120 volt output at 6000 watts and each of them weighs 140 lbs. You either need two of them, OR an autoformer to make a 120/240 split phase system.
Magnum also has low freq units as the transformers take up almost half of the space inside the unit.
Very few inverters on the market these days are the low frequency type.
you spoiled my interrogation. :DThey would use a PWM circuit running at higher frequency to create pulses of 48VDC, probably with a high-frequency inductor, generating a sine-wave current in the 60 Hz transformer.
The surge capability comes from how much current they can deliver from battery (plus transformer's ability to couple the power.)
I measure much of the current coming from battery as an AC ripple following the 60 Hz output. It isn't steady DC; the capacitors aren't big enough.
This wasn't at a 200% surge, just 40% of full load, but compared to average DC current the actual current swung from approximately 60% to 140%.