LO Posted October 21, 2002 Report Share Posted October 21, 2002 HiI am using a 16V DC walll adapter power supply for my Motor faders but once recified this voltage reads at 24V dc is this too high?Would I be better to return this power supply and use one around 12-14V ACT.I.A.LO Quote Link to comment Share on other sites More sharing options...
pilo Posted October 21, 2002 Report Share Posted October 21, 2002 If you are using a LM317 to regulate the tension, I think it's good, because you can have about 35VDC at the input...but! I think you get higher current if the input tension is not too high from the regukated one... say about 3V is good. Another thing, is that if you're regulated tension (at the output of the LM) is 12V under 100mA (this value are totaly random!!!!!!!!!!), the power used will be 12*0.1W... But if you have 24V at the input of the lm, the LM will dissipate 12*0.1W too!!!!! so you only used 50% percent of the power.... Quote Link to comment Share on other sites More sharing options...
LO Posted October 22, 2002 Author Report Share Posted October 22, 2002 mmmmm... Im a little confusedinput16v AC wall adapter(1.0-1.4A ?? cant remember!) Passes thru bridge rectifier & regulated with LM317 & 1K potrequired outputapprox8V with 1A(max) outputIt seems to be working OK I was just a little worried that my input may exceed the recommended? Quote Link to comment Share on other sites More sharing options...
TK. Posted October 24, 2002 Report Share Posted October 24, 2002 Hi Lo,it's really difficult with the specs for power supplies. Sometimes the effective voltage is given, sometimes not. Sometimes the voltage under load, sometimes not... however, the only interesting attribute is the output voltage under a current drain of 1A. If all motors are in standby mode, the current load is less than 1 mA, that's the reason why you see a higher voltage (before the LM317)Unfortunately the LM317 has to consume the difference voltage between the input and output. The result is heat. In fact the LM317 will get hotter with higher voltages, so if you have the option, take a power supply with 12-14V ACBest Regards, Thorsten. Quote Link to comment Share on other sites More sharing options...
LO Posted October 24, 2002 Author Report Share Posted October 24, 2002 thanks ;D Quote Link to comment Share on other sites More sharing options...
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