Hallo everyone, I'm testing a second-hand 12/1600 multiplus compact: by powering a hairdryer at intermediate power (600w) the inverter becomes very noisy (not from the fan), do you know what could be the cause? can it be solved?
I made a test with a second and third hairdryer, same problem.
Thanks for your help!
At intermediate power, that hairdryer, is using a diode for power reduction.
That diode makes the dryer to use only one side of the sinusoidal AC wave. (half-wave rectifying)
This functioning regime is quite nasty for any inverter and therefore that strange sound like a "growl".
Nothing to worry if the inverter is built OK.
Alex
thank you
Isn't there a risk of damaging the inverter?
Why doesn't another brand's inverter have this problem?
others use electronic transformers
Seconded. High frequency inverters with no transformer wont have the issue. Because of the physics involved.
Sorry to contradict, but this is a common misconception that HF inverters are "transformerless".
HF inverters have HF transformers. Otherwise they cannot "lift" the voltage from 48V to about 400V DC.
Only that the HF transformer is so small compared to a LF toroidal transformer that people peeking inside say "hey, look, no transformer". But the transformer is there.
Look below, the internals of the Multi RS inverter.
