Quick test of the PS-305D PSU


Mats did a review of the PS-305D PSU he bought from Smart-Prototyping:

I ran some basic measurements on the PS-305D (Linear 0-30V/0-5A, 1mA Display) I recently bought from Smart-Prototyping.The internal volt meter in the PSU seems reasonably well calibrated.Then I tested the Constant Current capabilities with having a direct short circuit through my DMM. It was very hard to adjust currents below 30mA, but that is expected in short circuit mode.  I connected a 12V led bulb with the PSU set at 12.0 volt output. Now the current could be adjusted reasonably well even below 30mAI then set the PSU to 5 volts and connected it to an oscilloscope to see how it behaved during power-on.

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  1. The negative spike should be easy enough to fix with a power schottky diode across the terminals.

    I suppose that when paying 1/10th of a proper PSU from Agilent one have to live with some “inconveniences”. But having a PSU that might destroy your project when turned on might be considered to be more than just an inconvenience :-)

  2. Should work fine as a constant current source for annodizing small objects. I’ll have to put a big note on it so I don’t use it for any sensitive circuits.

  3. Greetings from Norway. My friend from Poland got me one of these and fortunately I live to regret it.
    The ps was left over night and the print board burned badly. Do not buy this shit!
    If less fortunate you will fly off in a cloud of smoke to greet St Peter.
    Alive and Kicking the PS305D outa my house. Bad construction all the way !

    1. Eric, Two possibilities, moisture and lack of silicone grease on the heat sink. Power supplies are tricky.
      If you left it on overnight, current limiting should have protected it. Unstable A/C will wreak havok.

  4. This is a very old post.
    I bought the Korad KA3005P.
    Works fine (they updated it since Dave Jones’s post).

    There has been nothing from Matseng since the MH370 crash – I am worried.

    Mick M

  5. There was a fix for the turn off glitch posted on youtube. He added more capacitance to the control power supply. It seems that the caps on it were discharging faster than the caps in the power circuit (I suppose this would depend on the load.) When the regulator circuit lost power there was no control of the output.

  6. I can’t find the instructions right now, but I seem to remember reading do not turn on/off the supply with a load connected. I was going to ignore that, but after reading these posts it sounds like it may be in the instructions for a good reason.

  7. I just got one of these, and read the owner’s manual. The manual tells you to power on the supply, and then connect your load. If you follow the documented operating instructions then this is nothing to worry about.

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