Acer AL1912 LCD PSU fix

[otoluk]

Another LCD display with bad caps.

Symptoms: Dead, doesn't power on
Board: 715L1142-3-AUE year~2005



Fix: Replace bad Elite caps C814,C185 (16V 1000uF). Seems they fail sooner because are too close to heatsinks. It would be better to solder them not so close. Didn't replace the shield maybe it will help to stay cooler, is it safe? .

[JesseKnows]

Re: Acer AL1912 LCD PSU fix

You did not include a picture of the shield in question, so it's hard to be definitive. However, since a monitor is typically enclosed in plastic there is no danger of physical harm. However, shielding is used to prevent interference with other electrical devices, especially radios, cordless phones, cell phones and the like. You know, the FCC notice that we do not read in the manual!

[brethin]

Re: Acer AL1912 LCD PSU fix

You did not include a picture of the shield in question, so it's hard to be definitive. However, since a monitor is typically enclosed in plastic there is no danger of physical harm. However, shielding is used to prevent interference with other electrical devices, especially radios, cordless phones, cell phones and the like. You know, the FCC notice that we do not read in the manual!

He isn't asking about RMI shielding, he is asking about heat shielding so your off topic.

Caps are effected by heat yes, always replace caps in high heat areas with caps less prone to failure due to heat. Provided shielding is just that and rarely can be replaced with better shielding as far as heat goes, though adding some type of fan can help a alot.

[Agent24]

Re: Acer AL1912 LCD PSU fix

Mmm It's stupid how they put them above the heatsinks, so more heat can rise into them.

Maybe they do it to make sure the capacitors die off quickly? There's probably some black art to it to ensure it fails 1 week after the warranty expires...

[Radio Fox]

Re: Acer AL1912 LCD PSU fix

He isn't asking about RMI shielding, he is asking about heat shielding so your off topic...

Like JesseKnows, I also thought otoluk meant the RF shielding that covers the circuit boards, and agree with what he says.

What do you mean by heat shielding?

[Agent24]

Re: Acer AL1912 LCD PSU fix

I have never seen a heat shield on a monitor, I also think otoluk means RF shield.

[japlytic]

Re: Acer AL1912 LCD PSU fix

Good repair job, but I recommend replacing all of the electrolytic capacitors on the power supply board. You can replace the 400/450V unit if you want; it depends on the manufacturer and series.
With the electrolytics near the heatsink, you can place them lying against the board so that they are away from the heatsink, just like the 400/450V unit.

[otoluk]

Re: Acer AL1912 LCD PSU fix

You did not include a picture of the shield in question, so it's hard to be definitive. However, since a monitor is typically enclosed in plastic there is no danger of physical harm.

Yes, I meant the metal frame that covers board (RF shield). OK, next time won't throw it away.

Good repair job, but I recommend replacing all of the electrolytic capacitors on the power supply board.

I replaced all Elite caps, except the 400V one (but keep it in spare) , should update the first post accordingly. Monitor still works 24/7 at my workplace.