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Member #470157

Member Since: September 16, 2013

Country: United States

  • Got one and measured today, clear sky, 60F. Allowed a few minutes to warm and stabilize. Measured 9.62V Voc, 640ma Isc. Using a rough estimate of 0.7 for power factor gives maximum of 4.3W. We make a range of smartphone & universal charging products, which accept a wide range of inputs including solar modules - this one works fine. www.custompowersolar.com

  • Bought several of these to work with a Raspberry Pi, and after some fiddling using the dSPIN_raspi-master code was able to make it work driving a Nema 23 stepper, but the speed range only works in the 800-1200 range - anything slower stops suddenly, anything faster slips. Suggestions on how to tweak appreciated. Microstepping does work. Was able to get a cross-compiler environment set up in Eclipse as well as the onboard compiler. SAFETY NOTE!! I tried using the settings in the AutoDriver library - when I switched the overcurrent bridge function from enable to disabled (as it is in the AutoDriver library), a slow speed setting smoked the driver board, and destroyed my Raspberry Pi. DO NOT override the safety overcurrent shutdown features! The board runs hot enough as it is - setting the overcurrent shutdowns much past 4000mah is dicey at best, unless you have a good heat sink.


  • The best case real power output of this is 9.550.550.7, to get maximum power point in watts, or 3.7watts. You need to use that 0.7 factor on all these modules where they indicate Voc (open circuit voltage) and Isc (short circuit current). Please modify your listings - you don’t want customers to be disappointed when they found out they aren’t that high power.

No public wish lists :(