Hello to everyone, I wonder if anyone can offer some advice. I run a mobile disco and am frustrated with a ground loop problem. I have tried all the recommended solutions and some not recommended. I am about to build a custom power supply that will provide me with 19v 12v 9v 6v and 5v to power the numerous devices and peripherals I use.
After trying multiple different power supplies for laptops and peripherals some double insulated some not, connecting ground wires from each device and ground loop isolation transformers from the cheapest to the most expensive. I have failed to totally remove the hum. Grounding all the devices reduces the hum but does not eliminate it completely.
I did in a fit of desperation ground the negative on DC input to the laptop and this did reduce the hum even further, after thinking more I realised that was a really bad idea as any mains ground fault could end up in the laptop.
So this is my solution and what I would like some guidance with please. I have purchased a Meanwell 15a 24v PSU and will step down the voltages with 5 buck converters with appropriate ratings for the DC devices I intend to run from my new “Power Brick”
There are Three areas I would like advice on please.
Is it necessary, silly or advantageous to link the negative rail of all the buck converters?
Should I earth the buck converters on the DC side of the Meanwell or even ground it with a switch inline to create a ground lift?
I intend to install a fan in the “brick” enclosure that will house the 24vdc PSU and the buck converters. I would like to use a 240vac fan as I don’t want to run a potentially electrically noisy item anywhere on the DC part of the power brick. I would like if possible to control the speed of the fan. I am thinking of a 120mm 220-240v fan with a 0.1 amp draw. I did think of putting in a rotary switch with 4 of 5 positions and dropping through resistors but if I did my sums correctly the resistors will be huge (physically) So I then thought of using a capacitive dropper circuit for each position on the switch but in honesty I am struggling with this concept. Any advice would be very much appreciated.
Thank you
After trying multiple different power supplies for laptops and peripherals some double insulated some not, connecting ground wires from each device and ground loop isolation transformers from the cheapest to the most expensive. I have failed to totally remove the hum. Grounding all the devices reduces the hum but does not eliminate it completely.
I did in a fit of desperation ground the negative on DC input to the laptop and this did reduce the hum even further, after thinking more I realised that was a really bad idea as any mains ground fault could end up in the laptop.
So this is my solution and what I would like some guidance with please. I have purchased a Meanwell 15a 24v PSU and will step down the voltages with 5 buck converters with appropriate ratings for the DC devices I intend to run from my new “Power Brick”
There are Three areas I would like advice on please.
Is it necessary, silly or advantageous to link the negative rail of all the buck converters?
Should I earth the buck converters on the DC side of the Meanwell or even ground it with a switch inline to create a ground lift?
I intend to install a fan in the “brick” enclosure that will house the 24vdc PSU and the buck converters. I would like to use a 240vac fan as I don’t want to run a potentially electrically noisy item anywhere on the DC part of the power brick. I would like if possible to control the speed of the fan. I am thinking of a 120mm 220-240v fan with a 0.1 amp draw. I did think of putting in a rotary switch with 4 of 5 positions and dropping through resistors but if I did my sums correctly the resistors will be huge (physically) So I then thought of using a capacitive dropper circuit for each position on the switch but in honesty I am struggling with this concept. Any advice would be very much appreciated.
Thank you