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Electronics => Beginners => Topic started by: lots o tots on May 18, 2018, 01:34:08 pm

Title: 24v power supply basic question on 50% duty cycle. Voltage drop question.
Post by: lots o tots on May 18, 2018, 01:34:08 pm

I have 2 sperate 24v loads that will required to be turned on separately.  i am expecting the duty cycle to be about 50%.

I plan on buying a good power suplly such as a genuine mean well.

Since the duty cycle will be 50%, there will be some moments where 2 supplies are are on, but sometimes 1 will be on.

Will the supply voltage be the same in both conditions?  if they are slightly different, what can i expect a voltage drop to be?  ie. 1 load is 24.05V, 2 loads is 24.00 V.

I am trying to determine if the difference is negligable as the example i provided.
thanks
-LOT

Title: Re: 24v power supply basic question on 50% duty cycle. Voltage drop question.
Post by: sokoloff on May 18, 2018, 01:47:25 pm

Power supplies with internal feedback are generally good at maintaining output voltage on their output terminals. (Meaning: yes, it will be negligible, assuming you're staying within the spec of the power supply.)

After that, any common wiring will have voltage drops that vary with current. (If you go PS->common wire->relays/SSRs->individual loads, the common wire will have a higher voltage drop when both loads are on than when not. This is estimable, with voltage drop calculators on the web.)

In general, you are overwhelmingly likely to be fine, unless your loads are extremely picky about input voltages (and most are not, because the real world is imperfect so things are designed around that).