MDT STC-1280.01 noise

[Jeecha]

Have never used MDT KNX power supplies before, but my brand new STC-1280.01 (1280mA with diagnostic functions) is quite noisy compared to Meanwell and Gira power supplies I've dealt with before. The noise is typical high pitch coil whine and changes when there's bus activity. It is quite loud and audible throughout garage. However the distributor is not yet finished, so it does not have touch protection covers and doors installed yet. 640mA Meanwell test supply it replaced was completely inaudible from 3m away in same situation.

Is this normal, or should I be worried that my unit might be defective?

Thanks,
Jekabs

[hjk]

A little noise with a low load is normal. With higher load noise will be lower.

[Jeecha]

That could explain it - currently only the devices in distributor are connected (router, 3 switch actuators, 2 dimmers, 2 DALI gateways) and MDT power supply reports only 70mA consumption while idle. Total indoor line current, according to ETS and datasheets, will be around 1000mA when all planned devices are connected.

[Knochen]

I have the same mdt power unit myself.
Average load about 360mA.
No noise at all.