Is this voltage drop normal?

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Hi Michael,


The power supply you show is a variable 48V 480W SMPS. Thus, you can vary the output voltage much below the 48V which is the maximum. A voltage drop of 10V is possible and correct if you have adjusted the output voltage such.

I set the output voltage with no load (amp not connected) to 40V and then connect the amp and the voltage drops quite a bit. With no amp connected I can move the voltage adjustment pot all the way clockwise and the voltage is a bit greater 50V. If I then connect the amplifier the voltage is about 39V (and cannot be adjusted to be any higher).
 
My error. I didn't see the text as a link. You should be able to adjust the output to the full rated voltage.

As I said, I adjusted to full output voltage and then, after connecting the amplifier, the voltage reads more than 10V below what I had set it for and also cannot be adjusted to more than about 39V. So, at maximum setting the PS outputs more than 50V without the amplifier connected and with the amplifier connected it supplies less than 40V.
 
I set the output voltage with no load (amp not connected) to 40V and then connect the amp and the voltage drops quite a bit. With no amp connected I can move the voltage adjustment pot all the way clockwise and the voltage is a bit greater 50V. If I then connect the amplifier the voltage is about 39V (and cannot be adjusted to be any higher).

It is an SMPS. An SMPS cannot regulate without a certain load - that you may already know. I understand you are confused that with a load (the amplifier) the SMPS cannot get above 39V. But, an amplifier is not a resistive load. Would you have a power resistor of some 100-200 Ohm to test with? If the SMPS cannot give more than 39V in such a power resistor, I would return it as faulty. Just make sure first you really got the right 48V version (admitted, it is hardly the 24V version).


NB: MAACO is right, the specs and the three terminal power connector leave doubt about if the T3S is for a symmetrical or single supply voltage (both is ambiguously stated). My guess is that the T3S uses a single voltage and transforms a dual AC into a single DC voltage.
 
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