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treck87

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About treck87

  • Birthday 05/23/1987

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  1. Thanks David, As reference, I used an M.2 SSD heatsink that fit perfect in the gap bu I cannot put the front housing. I will update in a few weeks if everything run fine or I have issues again.
  2. Hi guys, I've received the transistors (MMSS8550 650mW) and replace all of them in CP (6 in total). See picture: https://drive.google.com/file/d/1Ov67EmCHTIKcjZax9ZtXYq5sXswFn9V_/view?usp=sharing Now all channels are working fine. In order to test my theory, I add a heatsink and one of the CP temp. sensor to the heatsink: https://drive.google.com/file/d/1Eu2gpqcnD9G3Mood6_GhxpPIZo20Gd8u/view?usp=sharing Running CP with my default set using 6 FANS of 3 Pins, the temp. increase really fast above 50ºC (It was running 30min. and temp still increasing) https://drive.google.com/file/d/1yxSJR9RptT5DWbWlaPC4JDVWpXvHn6Ci/view?usp=sharing I set all FANS to 100% where transistors shall have a min. power dissipation and temp. quickly drop below 40ºC (After 5min. temp. still dropping) https://drive.google.com/file/d/1bmq44mwGj3zmAVplj7DJ6pPLf9wBmmuT/view?usp=sharing As a conclusion, CP can come from the dark side replacing the transistors but you have to be really carefull when using 3 Pins FAN because of Power Dissipation. With this transistors (I'm not sure if factory one are 650mW or 350mW) you can run a 3 PIN FAN without constraint if Current Rating < 0.2 A. If current raiting is > 0.2A you shall use high RMP to avoid thermal issues. I hope that help people to fix their Commander Pro.
  3. If you can fit a TO92, it will provide better heat dissipation. The key is BJT is working as an amplifier in 3-pins mode. It means (rought aprox.) running FAN at 50% of RPM will drop 6V in transistor. If FAN is rating to 0.3A, it will be around (0.3/2)*6 = 900mW and these transistors are rating to 625mW so you will burn them. It's just an approximation but it's a valid one. Check your transistors with a lens and you will discover as they are burned
  4. Hi David, I'm waiting parts to arrive from eBay. As soon as I rework the device, I will post a short tutorial. The main issue with the device seems to be power dissipation in 3 pins fans. If you plan to use a 3 pins fan raiting > 0.2A, you need to ensure to run them at a min. RPM to avoid overheat these transistor. I will post more details when I make a deeper analysis. Regards
  5. Hi guys, I'm new in the forum but I just want to confirm the issue with transistors. After replace my Commander Pro using RMA, the second one has same issue: After a couple of days working fine, start to lose FAN Channels. I've lost 3 of them in my second device. I've checked the device and transistors are burning. I cannot touch them so it's more than likely that power dissipation is the problem. I've checked them with a polymeter and they are broken (Even you can see the SOT-23 Packet burned if you look close) I've orderer new transistors to replace myself and I've added a heatsink to the PCB. The heatsink is quite hot too. I will post with the result after replace the transistors but I think that heatsink is needed if you want to control 6 FANs of 3-Pins as I have. I'm electronic engineer so I know a bit about that. This issue will be only when use 3-pin fans because the commander pro needs to regulate the voltage of each fan so BJT transitors dissipate much more power than in PWM where they are always ON. I hope that this help other people. My fans are rated to a really low current ~ 0.15A.
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