Hi all,

I've got two led strips: a (A) 24V 167W RGB-CCT (6 wires) led strip and a (B) 24V 140W CCT (3 wires) led strip. I have tried to connect both to a Meanwell 200W power supply with a wifi rgb-cct controller in between that supports maximum 6A/Channel with a total maximum output of 15A.

There is a strange high pitch hiss sound coming probably from the power supply. I can hear this sound when putting the A led strip at maximum brightness and when I change brightness with the B led strip (from high brightness to lower one).

Do you know why there is this sound? could this be due to a not enough powerful power supply? or perhaps the problem is the controller?

I could also buy another power supply if necessary but I haven't found any rgb-cct controller more powerful than the one I've bought.

Thank you in advance

 

Welcome to AAC!

My guess is a poorly designed switching regulator.

 

If all LEDs are on the drain is about 300 W which a 200W supply will not like. Best to use a 350 - 400 W supply.

 

Welcome to AAC!

My guess is a poorly designed switching regulator.

Thank you!

A switching regulator? mmm you mean about the PSU?

It should not be so bad as PSU. The following are the specs:

Mean Well RSP-200-24 AC / DC

power supply 200W DC 24V MeanWell power supplies of the LRS series are a line of high performance professional power supplies , with a perforated aluminum structure, with air dissipation .
They are suitable for continuous use and are also suitable for use in the industrial field.
This power supply features overload, overvoltage and short circuit protection .

The power supply is equipped with a Volt regulator (Vadj) which allows for an output voltage from 20V to 26.4V.
It is compatible with all led strips and devices withconstant voltage DC 24V .

FEATURES:
- Power: 201.6W
- Maximum Current: 8.4A
- Driver type: AC / DC
- Input voltage: AC 85-264V
- Output voltage: DC 24V
- Dimmable: no
- Number of outputs: 3 outputs
- Structure : aluminum
- Degree of protection: not waterproof IP20
- Operating temperature: -30 ° C + 70 ° C
- Effectiveness: 89.5%
- Dimensions: 215 x 115 x 30 mm
- Warranty: 3 years
- Certificates: UL60950-1, TUV EN60950-1 approved,
Compliance to EN55022 (CISPR22) Class B, EN61000-3-2, -3,
Compliance to EN61000-4-2,3,4,5,6,8,11, EN55024,
light industry level, criteria TO

 

If all LEDs are on the drain is about 300 W which a 200W supply will not like. Best to use a 350 - 400 W supply.

I'm not using both led strips at the same time. It's this the strange thing.. only one per time.

 

Hiss or high pitched whine is caused by the Inductor or Transformer being over driven.

 

for the "over-driven" thing, a more powerful PSU should be enough to fix it.. 250W still too low in your opinion?

 

I have an update. I've bought a new PSU (same brand of the other). This time 320W and IP65. No coil whine at all.
I have to understand now why the other PSU produces that noise at max brightness.

I would exclude now the controller. Two options are left:

1) it's because the PSU is not powerful enough
2) it's because the case is IP65, so that might reduce the noise
3) both of them

What do you think about?