Hey guys. I don't have much experience with primary side of SMPS circuit. Most faults I get are on the secondary side. When testing AC on the SMPS primary side, do I use the negative leg of the filter cap for ground. I am testing the 120VAC to see where I lose it, since its not getting to the bridge rectifier. I don't have a schematic.
Testing AC on SMPS
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Re: Testing AC on SMPS
You need to test the ACV BETWEEN the two ~ pins of the Bridge rectifier with ACV meter to find out if the incoming AC reach the Bridge rectifier ~ pins or not, the Negative legs of the main filter cap is the GND ref of the primary side circuit which is AFTER the bridge rectifier (+/- OUTPUT of the bridge).
Show us the pictures of top and bottom side of the board so we can see the path of the incoming AC.Last edited by budm; 09-01-2016, 12:58 PM.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809 -
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Re: Testing AC on SMPS
Can we see the straight shot pictures of the whole Top and Bottom side of the board? The AC to the ~ of the bridge may being fed through the relay but I cannot tell until I see the pictures of the whole board.
What is the make and model of this board?
I assume you already test the fuses.Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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Re: Testing AC on SMPS
yup I tested the fuse. The TV model is Samsung PN51D550C1FXZC. I can't take decent pics with my camera so SJ link below.
Board part number is bn44-00444A.---
https://www.shopjimmy.com/samsung-bn...upply-unit.htmComment
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Never stop learning
Basic LCD TV and Monitor troubleshooting guides.
http://www.badcaps.net/forum/showthr...956#post305956
Voltage Regulator (LDO) testing:
http://www.badcaps.net/forum/showthr...999#post300999
Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl
Tear down pictures : Hit the ">" Show Albums and stories" on the left side
http://s807.photobucket.com/user/budm/library/
TV Factory reset codes listing:
http://www.badcaps.net/forum/showthread.php?t=24809Comment
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