Lab. ispravljac 0-30V 0.002-3A
Moderators: pedja089, stojke369, [eDo], trax
Re: Lab. ispravljac 0-30V 0.002-3A
Sta treba mijenjati ako hocu staviti trafo od 18VAC ?
Re: Lab. ispravljac 0-30V 0.002-3A
Evo najnovije verzije ovog napajanja koju sam našao na EL forumu,
neznam zašto ne osviježe i projects stranicu s njom....
Na njihovom forumu mozete procitati da nekima napanja nisu radila i da
se tranzistori pregrijavaju kao i otpornici(vidjet cete na shemi da su 1/4W
otpornici zamijenjeni 2W otpornicima).
E sad ako netko ima vremena neka napravi PCB ili ga pokuša iskopati na netu.
neznam zašto ne osviježe i projects stranicu s njom....
Na njihovom forumu mozete procitati da nekima napanja nisu radila i da
se tranzistori pregrijavaju kao i otpornici(vidjet cete na shemi da su 1/4W
otpornici zamijenjeni 2W otpornicima).
E sad ako netko ima vremena neka napravi PCB ili ga pokuša iskopati na netu.
- Attachments
-
- PSU.rar
- (65.29 KiB) Downloaded 584 times
Re: Lab. ispravljac 0-30V 0.002-3A
Izgleda da nismo bas nesto aktivni u ovim ljetnim mjesecima,
nitko ne odgovara na post,
morati cu ja da napravim PCB....
nitko ne odgovara na post,
morati cu ja da napravim PCB....
Re: Lab. ispravljac 0-30V 0.002-3A
Na dnu sajta projekta:
Received the following email from Ivan on 02/2010:
Ok. I bulid your project about a day ago. Mounted all the parts on the pcb and then concluded that there is some serious problems in this schematics. First, 2N3055 will overheat, so you have to connect two of them in parallel with emitter resistors 0.1ohm/5w. Second, maximal voltage between '+' and '-' of TL081 is 36VDC.If you connect them as it is shown in this circuit diagram that voltage will be about 45VDC, so they will burn down immediately. To fix this problem you have to reconnect all pins number 7 of U1, U2 and U3, emitter of Q3 and 'upper' end of R19 to out of an 7809 with 18V zener diode between 'common' pin and '-' of 3300uF cap, and input of 7809 connect to '+' of the same cap. Now, on pin number 7 and mentioned parts you'll have 27VDC, and total voltage will be 32.6VDC. Third, instead of using 3300uF, use 4700 or 6800uF/63VDC to reduce the ripple on higher currents (2-3A). The rest of the circuit is perfect. I like it cause it is so inexpensive and easy to make with those simple reconstructions i mentioned.
Received the following email from Ivan on 02/2010:
Ok. I bulid your project about a day ago. Mounted all the parts on the pcb and then concluded that there is some serious problems in this schematics. First, 2N3055 will overheat, so you have to connect two of them in parallel with emitter resistors 0.1ohm/5w. Second, maximal voltage between '+' and '-' of TL081 is 36VDC.If you connect them as it is shown in this circuit diagram that voltage will be about 45VDC, so they will burn down immediately. To fix this problem you have to reconnect all pins number 7 of U1, U2 and U3, emitter of Q3 and 'upper' end of R19 to out of an 7809 with 18V zener diode between 'common' pin and '-' of 3300uF cap, and input of 7809 connect to '+' of the same cap. Now, on pin number 7 and mentioned parts you'll have 27VDC, and total voltage will be 32.6VDC. Third, instead of using 3300uF, use 4700 or 6800uF/63VDC to reduce the ripple on higher currents (2-3A). The rest of the circuit is perfect. I like it cause it is so inexpensive and easy to make with those simple reconstructions i mentioned.
