Re: Sharp LC-60LE600U tries to turn on, faults, DIAGNOSTIC DONE BY THE NUMBERS!

What is the fault bypass procedure?

Thanks!

Re: HP D530 USDT power supply HP-L1520F3P

Problem solved! Found that cap C801, a 22uF/50V was defective (read 2.2uF). This cap connect across the two traces that come from the main supply. The STANDBY now reads ~5.1V with no load, 5 ohm, and 2.5 ohms.

Later!

Jim

Hello,

I have a HP D530 USDT (P/N: DB670AV#ABA) PC with a HP-L1520F3P power supply. This supply when down yesterday. I found about 6 swallow caps that I changed. The supply came back up but the STANDBY voltage goes from 5V to 6V when the main supply is turned on (green wire grounded). This will cause the 5V protection zener on the STANDBY line to short. Looking at the PCB traces it looks like the main supply is somehow connected to the STANDBY SMPS chip on the hot side. I have a 5 ohm load on the STANDBY line. Adding another 5 ohm load (2.5 ohm) will drop the STANDBY voltage to...

Re: Antec SL300S Standby Voltage high.

BTW, that 47uF (C8) read about 5nF on my cap tester!

Jim

Re: Antec SL300S Standby Voltage high.

Thanks for all the input! Here is an update.

Changing C14 (22uF 50V) lower the STANDBY to ~5.7V. Changing C8 (47uF 25V) did the trick, STANDBY now reads 5.10V.

I'll now change the remaining small caps.

BTW, I did find the the main supply would not turn on until the STANDBY voltage was =< ~5.5V. Also, the STANDBY would start out at ~6.3V and then slowly fall.

I was thinking about the zener across the output myself. Is there a low voltage MOV that would work better or faster?
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1st, I know... just dump it

I have a Antec Smart Power SL300S that the standby voltage is reading ~6.35 unloaded. If I load it the voltage drops to ~5.0V:

10 ohm load output is 5.08V
5 ohm load output is 5.07V
2.5 ohm load output is 5.05V

This unit had bad Fuhjyyu caps on the +3.3, +5.0, and +12.0V rails. It was working in my dad PC until the fan stopped work. When I when to change the fan I noticed the bad caps. It sat in the to do pile until now. After changing the caps and testing I noticed this STANDBY voltage issue.

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