I recently got some mean well LRS PSUs for my siren project thinking that they would be better and smaller than the crap ebay ones that I was using. To my dismay, they have considerable coil whine. I think the problem could be resolved by increasing the PWM frequency on the chip that is on the daughterboard as the whine follows the flashing of the big red led on the daughterboard. Does anyone know if this is possible and if so, how? Or if you have any other suggestion, that would be very welcome and appreciated.
I guess if you wanted to just kill it with load you could just get a power resistor and dump heat into that as needed, right? Maybe even with one of those cheaply available IRF520 boards? From a quick look it seems like you can pull the current current (sorry!) from observersensor and then decide when to switch the extra load on and off. So much waste.
I might be mistaken, but the current drawn is not an input parameter but a feedback measurement. You can’t tell it to use a fixed or minimum amount of current, that’s not how ohms law works. The windings are what they are, and the voltage available is what it is. Maybe whatever you are trying to do needs enough current or power to cross that noise point, but I am assuming that’s not the case if you are here!
There are so many different ways to do AC to DC supplies that asking for a global way to increase switching frequency can’t be answered, plus all that hardware on the PCB will be tuned around what it’s currently running at. After a certain wattage the power supply should have a boost PFC in front of what could be many different switching topolgies. No single answer there, I honestly wouldn’t try.
My advise, if you can fit it, look into used server power supplies. They are so much higher quality than cheap AC/DC supplies, and if all you need is 12V, 48V, or ~55V super easy to find.
Thanks! Admittedly. At this point, I am looking for a quick fix here. I bought the mean well thinking they would be better than the cheapos I had. I would not even have time to get the right resister for doing a load dump, hence me asking if I can use the controller itself to dump the load maybe by holding torque at idle until and low velocity until a target velocity that pulled enough current was requested and reached.
In the long run, I was looking at server power supplies. But I was hoping for something with a smaller form factor as eventually I will need to travel with three of them.