Issue with Meanwell RT-50b ? (solved)

Hi Everyone,

I just finished my DIY case to get into Eurorack world. It is meant to be powered by a second hand RT 50b I got sometime ago.
I decided to start testing cheap modules first in order to make sure everything is fine before blowing up expensive stuff but I quickly ran into a weird behavior coming from a A 160 clock divider. Most steps remain lit constantly even without clock in. :confused: The module, which is also second-hand, has been tested later on another system and seem to work normally.

I’m noticing some audible high-pitched buzz coming from the PSU when it’s powered up so I’m wondering if this is its normal behavior ?

I know there are RT-50b users out there that can share their experiences :wink:

Thanks in advance !

Did you measure the voltages on your busboard? I’ve been running 2 meanwells without any problems for about 2 years.

Yes that’s the first thing I did even before plugging modules.

How many modules you have connected?
Switching PSU’s needs some load to operate.

I’ve only connected one or two module at a time so far.

I have no problems with meanwell PSUs. I guess you should just connect a few more modules (or high-wattage load resistors for testing, if you have some)

Ok I might try that after someone can confirm that it’s normal that you can hear some noise coming out of the RT 50b when it’s on if you get close enough :slight_smile:

Yes, the high pitched noise from the meanwell is normal when it doesn’t see enough load. It needs a minimum load on the +5 V and +12 V rail.

I had this too. The noise goes away when you add more modules and the load on the PSU goes up.

Ok thanks a lot i will give it a try with more modules.

I’ve plugged everything and the noise seems to be gone now.
The clock divider is also working fine even though its leds remain lit when it’s not triggered for some reason.

Now I just need more modules to let the real fun begin :smiley:

> when it’s not triggered for some reason.

It’s the normal behaviour. The module has no way of detecting that nothing is plugged into the clock input. It cannot make the difference between “nothing is patched into the input” and “a super slow clock is patched and is staying forever at 0V”.

It looked different in that demo as well as in my friend’s system so that’s why I freaked out