electronics, repairs, service manuals and datasheets discussion community for the repairs professionals and technicians
FAQSearchMembersGroupsRegisterProfilePM'sLogin/Out
Switch Mode PSU

 
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Equipment Repairs
View previous topic :: View next topic  
Author Message
miox
Guest





PostPosted: Mon Jul 07, 2008 6:22 pm    Post subject: Switch Mode PSU Reply with quote

hi there, i have a 24 volt switching power supply that has fried its quad opamp "LM324N" i did replace the chip but it still got fried, i measured the output of the psu and it was over voltage by 200% "70-75 volts" i did check some parts eg, capacitors and resistors and some diodes and its all ok, can any one pls help tnx
Back to top
vtech



Joined: 08 May 2006
Posts: 1264
Location: USA

PostPosted: Tue Jul 08, 2008 3:58 am    Post subject: Re: Switch Mode PSU Reply with quote

miox wrote:
hi there, i have a 24 volt switching power supply that has fried its quad opamp "LM324N" i did replace the chip but it still got fried, i measured the output of the psu and it was over voltage by 200% "70-75 volts" i did check some parts eg, capacitors and resistors and some diodes and its all ok, can any one pls help tnx


Depending on your circuit design, sounds like you may have somehow lost a feedback signal which could be many things?-w/out a diagram, it is not going to be easy. Over 200% increase in output during failure? Wow Not a very good design I might add!?
Not sure if I'd even trust using such a device as it will likely damage whatever is powering. Wink
Back to top
View user's profile Send private message
miox_24



Joined: 07 Jul 2008
Posts: 5

PostPosted: Wed Jul 09, 2008 6:22 pm    Post subject: Reply with quote

Very Happy
Back to top
View user's profile Send private message
miox_24



Joined: 07 Jul 2008
Posts: 5

PostPosted: Wed Jul 09, 2008 6:29 pm    Post subject: Reply with quote

Very Happy yes sir ur ryt, i found & replaced a deffective shunt regulator "TL431" in the reg ckt. thanks a lot
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Electronic equipment repair and service manual search discussion Forum Index -> Equipment Repairs All times are GMT
Page 1 of 1

 
Jump to:  
You can post new topics in this forum
You can reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


eServiceInfo on FB - Service Manuals Free Download - Service Diagrams

Free TV Schematics Download - HARDW.net - Pinout Master - Jabse Service Manual Search - Jabse.InK  - onTap.bg

SnimkiOt.com - Poblizo.com : пътешествия