How Steady is you Meanwell PSU?
 

I recently set up a TEC H20 system and I'm using the Meanwell to power my 220w TEC. The voltage coming out of the PSU seems less than steady, however. I've been taking measurements every few minutes and I'm seeing some interesting fluctations. I'll set the psu to around 13volts, then 5 minutes later, it may be around 12-ish, or sometimes even 14-15v.

Now its been pretty hot around here lately and the PSU casing is getting pretty dang hot, so I'm assuming the compontents are getting hot and simply not regulating consistantly. So my next question would be: have any of you modded your MeanWell PSU's? I'm thinking of adding some additional cooling, or at least cutting out that fan area and replacing it with a wire grill.

-Nep

Welcome!

The pelt can handle some voltage variations, without a hitch, as long as the change is very gradual.

If you're having to constantly adjust the output, that's another problem.

Hey Neptune5K,

I have used several of the Meanwell PSUs with TECs. Both a SP-320-12 and S-300-12 with a 226 watt was very stable. I could easily adjust the voltage in 0.5 V increments and hold it there for several hours. The voltage will change initially as the Pelt cools down but once the temp stabalizes the voltage should to.

As a Pelt changes temps it will induce a reverse voltage onto the DC power source (Seebeck affect).

Try setting your voltage once the TEC has reached equillibrium - then it should be solid. If not, something may be wrong. Do you have good tight connections on all the leads?

Good luck,