Multicolour LED Basin Mixer/Faucet - 240V Power Supply

[Billy22Bob]

I bought this faucet which is designed to run on 6V made up of 4 x 1.5V batteries.
**broken link removed**

I estimated the unit wouldnt drag any more than 100mA and checked with the supplier that this was the case and that a 240-6V DC power adapter would be suitable to replace the battery pack. Confirmed.

Installed the unit and its fine except for 1 thing.
The colour changes with temperature limits - blue for cold, green for warm red for hot and red flashing for very hot.
The blue, green and red are fine - however the red flashing is "stuttering" for want of a better description. It flashes intermittently at high rates as opposed to a steady 300ms flash when under battery power.
It only does it on the PS and not the 6V battery pack.

I suspect I bought and am using a switched mode PS (very light). Would this be causing the stuttering or would I be better to upgrade to a 200mA unit?....or both.

 

[#12]

I think adding a fairly large capacitor (about the size of a grape) to the output of the power supply will help it stop responding to the sudden changes in the load current. Maybe 2.2 to 3.3 ohms in series with the supply voltage, then a 220 uf/10v aluminum electrolytic capacitor. It might work with no resistor at all.

ps, have you measured the actual current load? What is the amperage rating of the power supply? I don't expect these to be the problem, but verifying that you actually have what you expect is always a good thing to do.

 

[KeepItSimpleStupid]

Peak currents may be causing the problem.

Is the power supply isolated?

 

[Billy22Bob]

pardon my ignorance....isolated...

not sure what you mean by isolated.
It runs off my 240V in a power point connected to my power point supply.

On the capacitor/resistor idea....would that cause some back emf if the LEDs were flashing (as they are supposed to do when >55deg)?

Thought of measuring peak currents - difficult to measure (hand held digital meter) in this state as they flash on and off so quick.

 

[KeepItSimpleStupid]

Isolated - No connection to N or L of the AC line. Meaning there would be no shock hazzard if a component failed.

Peak or steady state currents may be causing the switching power supply to shut down. Take the battery source and place a low value resistor that could read something on your DVM with the expected currents.

e.g. If you can read 0.1V and the expected draw is around 100 mA, then chose R to be =0.1V/0.1A or 1 ohm and measure the voltage across the resistor. We already know that likely the power supply has issues.

What it probably has a time driving is the valve.

You can tray a 100uf capacitor in parallel with the supply. This will help peak currents.

What size are the batteries, "D"? This would suggest that you could get 1 Amp out of the battery for short times.