Annoying PWM sound from Xantrex inverter
I finally got my Xantrex ProWatt SW 2000 installed into my rig.
Functionally, everything seems great. I can run the hair dryer (on 800W setting anyway) and microwave at the same time.
I finished setting it up after sundown and did my initial testing in the dark. The next day, sun shining on entering my rig, I could hear an annoying buzzing sound coming form the inverter. The inverter is completely off at this point.
A bunch of testing seems to indicate that the sound occurs when my PWM solar controller (Samlex 30A) goes into current limiting mode (i.e,. absorption aka CV stage) the noise starts. The controller uses PWM at this stage and it seems that the fluctuating voltage/current causes some kind of resonance in the inverter.
I'm not entirely sure if this is normal, but I'm certainly loathe to try to send this guy away for repair.
It's worth noting that when I turn on the dimmable lights in the coach, I can also hear the PWM noise and it varies with the dimmer position (it's a PWM type dimmer). On one of the two dimmers, even the top (fully on) position still has some noise.
Any ideas to get rid of the noise? Do MPPT controllers have PWM-like/switching behavior when they are limiting current?
Functionally, everything seems great. I can run the hair dryer (on 800W setting anyway) and microwave at the same time.
I finished setting it up after sundown and did my initial testing in the dark. The next day, sun shining on entering my rig, I could hear an annoying buzzing sound coming form the inverter. The inverter is completely off at this point.
A bunch of testing seems to indicate that the sound occurs when my PWM solar controller (Samlex 30A) goes into current limiting mode (i.e,. absorption aka CV stage) the noise starts. The controller uses PWM at this stage and it seems that the fluctuating voltage/current causes some kind of resonance in the inverter.
I'm not entirely sure if this is normal, but I'm certainly loathe to try to send this guy away for repair.
It's worth noting that when I turn on the dimmable lights in the coach, I can also hear the PWM noise and it varies with the dimmer position (it's a PWM type dimmer). On one of the two dimmers, even the top (fully on) position still has some noise.
Any ideas to get rid of the noise? Do MPPT controllers have PWM-like/switching behavior when they are limiting current?
