Forum: Troubleshooting Computer Displays
Today, 11:14 AM
|
Replies: 661
Views: 355,761
Re: Samsung Syncmaster 225BW
I would check the ESR of those surface mount electrolytic capacitors.
Probably after all these years with heat they are bad.
|
Forum: Troubleshooting Game Consoles & Other Weird Devices
Today, 09:18 AM
|
Replies: 5
Views: 60
Re: Xbox 1.6 Motherboards and Polymer Capacitors
It might be worth it to measure the voltage on those caps and if it is low enough use 2.5v 3300µF polymer caps:
They are not in old recommendations simply because they did not exist back then....
|
Forum: General Electronics Technical Discussion
Today, 01:32 AM
|
Replies: 3
Views: 47
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-24-2022, 11:56 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
I would say it is still starved for power, but you really should check the integrity of the APFC swiching mosfets (Q11/Q12 & Q1/Q3 from the schematic kaboom posted) if you do suspect that the supply...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-24-2022, 03:50 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
What voltage do you read on the primary capacitor during this test?
If your line voltage is 230VAC then it should be around 230VAC x √2 = 325VDC in standby.
And when you start it up it should be...
|
Forum: General Capacitor Questions & Issues
06-21-2022, 10:28 AM
|
Replies: 6
Views: 162
Re: Cleaning up capacitor leakage
I would recommend cleaning using acetic acid if it leaked on the board.
Every time I do I can see bubbles and hear fizzing as I put it on the areas with leaked electrolyte, so it does a chemical...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-21-2022, 09:52 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
As I explained in my previous post it will be different for each PSU design.
What works on this one will obviously not work on another with a different APFC controller and there are many of those!
...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-20-2022, 01:35 PM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
It is disabled, but as stated in the datasheet you can't be sure it has 0% duty cycle.
It is better to desolder the OVP/EN pin as that has the sole purpose of enabling the circuit.
Every power...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-20-2022, 08:00 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
Try to increase to a 120w bulb, you can of course use two parallel 60w bulbs instead...
Also note the remark in the datasheet about grounding the SS pin:
Note: In an open-loop test circuit,...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-19-2022, 03:17 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
Ok, the original Samxon capacitor is fine, remember that capacitors have a +/- 20% tolerance rating...
To test the power supply without APFC you can either ground the UCC3818N APFC controller...
|
Forum: Troubleshooting Audio Equipment
06-18-2022, 02:03 PM
|
Replies: 86
Views: 1,515
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-18-2022, 03:14 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
45.2,14.4 (https://www.google.com/maps/place/45°12'00.0"N+14°24'00.0"E) is in the Adriatic Sea, so I would guess 230VAC on a raft between Krk and Opatija :D
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-18-2022, 03:04 AM
|
Replies: 54
Views: 1,576
Re: Cyberpower CP900EPFCLCD - F03 Error
Well you probably will not find that on sites like eBay, what you need is some basic electronic components.
They could even be harvested from some old PC power supply for example.
But ST also...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-18-2022, 01:21 AM
|
Replies: 28
Views: 634
Re: Learning with ATX CHIEFTEC 450W PSU
Usually when you hear sounds like you describe it can be caused by a failing primary bulk capacitor.
So I would try to measure the primary capacitor for both ESR and capacitance.
It might just be...
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-17-2022, 10:27 AM
|
Replies: 54
Views: 1,576
Re: Cyberpower CP900EPFCLCD - F03 Error
There is not much use to test it without the transformer, the issue likely lies in or after it.
But sure, I don't think it would hurt, especially if you use the light bulb for current limit...
...
|
Forum: Equipment Usage, Soldering, Techniques, and Reviews
06-17-2022, 10:22 AM
|
Replies: 10
Views: 236
|
Forum: General Electronics Technical Discussion
06-16-2022, 09:40 AM
|
Replies: 41
Views: 1,689
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-16-2022, 09:26 AM
|
Replies: 54
Views: 1,576
Re: Cyberpower CP900EPFCLCD - F03 Error
Well one thing you could do then is desolder the transformer and build a circuit from the Viper datasheet using it:
They do provide an example circuit in there for a charger...
And yes I meant to...
|
Forum: Troubleshooting Desktop Motherboards, Graphics Cards, and PC Peripherals
06-13-2022, 02:34 AM
|
Replies: 4
Views: 174
Re: MGX7520 onboard graphics problem
Now that you have two identical board a nice way could be to use a thermal camera to look for any hotspots that are not the same between the units.
|
Forum: Troubleshooting Power Supplies and Power Supply Design
06-10-2022, 11:50 AM
|
Replies: 52
Views: 19,281
|
Forum: General Electronics Technical Discussion
06-09-2022, 11:54 AM
|
Replies: 7
Views: 175
Re: Can halogen bulb flicker?
This type of lamp with the two small pins is notorious for developing a bad connection!
Either the pins oxidize or the contact receptacle do, or the springs in the receptacle become too weak causing...
|