Any harm in increasing capacitance?

[Mad_Professor]

Long story short, I replaced some 220 25v NXB caps with 470 25v HE caps.
I didn't have correct caps in stock and used what I had in stock and replaced caps just to get the damn thing working.
TV works fine. I plan on getting correct caps soon.

But I was wondering any ill effects?

[rhomanski]

Re: Any harm in increasing capacitance?

Only if something can't handle the inrush currant, probably. Without more information such is it a timing circuit? Could take longer to charge and do something. Otherwise, if it works fine, probably not.

[Mad_Professor]

Re: Any harm in increasing capacitance?

Only if something can't handle the inrush currant, probably. Without more information such is it a timing circuit? Could take longer to charge and do something. Otherwise, if it works fine, probably not.

That what I was wondering, the circuit in question seems to be providing 12/24v rail for the inverter and/or mainboard. It didn't fix the problem, I only replaced it because capacitance read nonexistent on one of them with my klein dmm.

I got a samsung TV that randomly turns itself on or off. Very annoying when you're sleeping all suddenly a bright light comes on in the room and they are talking about diet pills.

[rhomanski]

Re: Any harm in increasing capacitance?

I guess you've already checked for practical joking little brothers, neighbors, girlfriends or wives. I have to say I've seen some ghost/demon movies start this way, maybe a priest?

[stj]

Re: Any harm in increasing capacitance?

probably a bad standby button.

[rhomanski]

Re: Any harm in increasing capacitance?

Yeah, or power button whatever you want to call it. You can try cleaning it with some deoxit d5.

[FLIPPARD01]

Re: Any harm in increasing capacitance?

The best information and specs that I have found is through the manufacture guidelines themselves. See the following attachment.

[sam_sam_sam]

Re: Any harm in increasing capacitance?

I have a AOC brand TV set that use to not want to turn OFF
When hit the power button and the tech that came said the the switch board was bad
This set was only 18 months old at the time

I had an exstend warranty on this set and then they told me that the switch was no longer Avable any more I got a refund on what I paid for the tv and exstend warranty

I used for another year with the switch board disconnect and used the remote
Then I move this tv to our office and did not want to have use the remote to turn it ON and OFF

So I open the TV set and check all of the caps on the power board and the board controller and found that every cap that was below 100uf had a very high ESR value compared to a new one and after I recaped both board I could use the switch board that was on the set
Now it turn ON and OFF like it should

I hope this helps

[ZnsaneRyder]

Re: Any harm in increasing capacitance?

I find they don't use enough capacitance in the first place! I usually upgrade 220 to 470, and 470 to 680......820 to 1000, etc.

THINK ABOUT THIS, a TV has for example a 470uf that is under high stress, so over time the ESR gets worse, and the cap falls to 400uf or less and the TV stops working. Now if you use a 680uf in the same place, and it falls in value over time, it will still be higher uf than the original cap when new and the TV will still work! Also higher uf caps have lower ESR.

In MANY TV, on a DC output where they will have a large primary cap, then a ripple filter made with a small coil, then a 47uf secondary cap after the coil, I will take out the 47uf and replace with a cap as big as the primary cap, I have had complete success with that as well.

You can upgrade capacitors with no problem as long as it is for power supply circuits. (not timing or other as previously mentioned)

I usually try to keep the uf value the same or close during an upgrade, but in some situations I have upgraded 470 with a 2200 for a Plasma TV that really stressed the caps and they were near heatsinks.

I find bigger caps make some TV start faster.

[sam_sam_sam]

Re: Any harm in increasing capacitance?

I find they don't use enough capacitance in the first place! I usually upgrade 220 to 470, and 470 to 680......820 to 1000, etc .

When would this not be a good idea to do this in a switching power supply ?

I know that changing the value on caps near the switching IC chip not a good idea because that dose change timing of the circuit I did it once on a power supply that was not right from the beginning but I did find a value that work better than the one that was in it

[japlytic]

Re: Any harm in increasing capacitance?

With increasing capacitance of electrolytic capacitors, I have quite good judgement on what units can have a capacitance increase, and I also have typical minimum capacitance/voltage recommendations on a particular supply rail for particular devices (or classes thereof).

[sam_sam_sam]

Re: Any harm in increasing capacitance?

Can you go more details about this I would like to learn about this
Thanks

[CapLeaker]

Re: Any harm in increasing capacitance?

Do you mean the starting cap?

[sam_sam_sam]

Re: Any harm in increasing capacitance?

"[I also have typical minimum capacitance/voltage recommendations on a particular supply rail for particular devices (or classes thereof)."


I want to know more about this

[japlytic]

Re: Any harm in increasing capacitance?

My minimum recommendatations for two classes of products:

Recommended minimum electrolytic capacitor values for set-top boxes:
+3.3V: 1000uF 6.3V (without hard disk recorder), 2200uF (with hard disk recorder)
+5V: 1000uF 10V (without hard disk recorder), 2200uF (with hard disk recorder)
+12V: 470uF 16V (without hard disk recorder), 2200uF (with hard disk recorder)
-12V: 470uF 16V.
Voltages between 6 and 12V: 470uF 16V
VFD –ve supply and heater or Tuner (around 30V) supply: 100uF 50V
LNB supply (typically around 22V): 470uF 35V.
Primary side low voltage: 100uF 50V
Primary 400/450V unit: 47uF 400V (without hard disk recorder), 150uF 400V (with hard disk recorder)

Recommended minimum electrolytic capacitor values for DVD/HD-DVD/Blu-Ray players:
+3.3V: 1000uF 6.3V (DVD), 2200uF 6.3V (earlier HD-DVD/Blu-Ray; otherwise 1000uF)
+5V: 1000uF 10V (without IDE/SATA loader), 2200uF (with IDE/SATA loader)
+12V: 470uF 16V (without IDE/SATA loader), 2200uF (with IDE/SATA loader)
-12V: 470uF 16V.
Voltages between 6 and 12V: 470uF 16V
Tuner supply (around 30V) or VFD –ve supply and VFD heater: 100uF 50V
Primary side low voltage: 100uF 50V
Primary 400/450V unit: 47uF 400V (without IDE/SATA loader), 100uF (earlier HD-DVD/Blu-Ray without IDE/SATA loader; otherwise 47uF) 150uF 400V (with IDE/SATA loader)

[Viperel]

Re: Any harm in increasing capacitance?

Would increasing the capacitance in an ATX SMPS lead to any issues? I want to upgrade some 220uu/16v to 470uf and the 1000uf/16v to at least 1500uf. As ESR goes down with capacity i take it this could be beneficial (as long as it's not too low).

I want to know as the original caps (5 years old) are going bad as all voltages seem to drop almost 5% under load which is at the edge of the ATX quality standard, and was wondering if i could also "upgrade" them with higher values, as high quality PSUs are using 2200/3300uf 16V caps.

And i think i got my answer here https://www.badcaps.net/forum/showpo...0&postcount=67

[kc8adu]

Re: Any harm in increasing capacitance?

check for a lost remote stuck in the sofa.
seen that more than once.

I got a samsung TV that randomly turns itself on or off. Very annoying when you're sleeping all suddenly a bright light comes on in the room and they are talking about diet pills.

[mariushm]

Re: Any harm in increasing capacitance?

Larger capacitors suck more current at start-up, which in extreme cases can trip fuses or even damage diodes that are part of rectification.

Some badly designed power supplies could have badly sized time delay fuses. A very large primary capacitor could "suck in" 40-50A for a very brief moment, and that could be enough to trip the fuse in your house electricity panel. Some power supplies have circuits which add PTC or NTC resistors in series with mains power to limit the inrush current and relays to take out these resistors after a second or so, some don't.

japlytic's comments are just plain bad advice.. there's all kind of power supplies with various designs and which use various control chips. You just can't generalize.

A switching power supply running at 1Mhz+ may not need as much output capacitance as one running at 100kHz .. a lower uF value polymer capacitor would work better than bigger larger electrolytic capacitors.

Also, in some circuits and with some switching regulators / controllers, too low ESR can hurt the circuit and cause it to oscillate, overheat, behave badly under some conditions. If you don't know how the circuit works, try as much as possible to use same replacement components as close as possible in specifications to the old parts.

Have a look at those Delta or HP server power supplies which use some awesome transformers and circuitry in general... here's an example of a 2450w power supply : https://www.youtube.com/watch?v=nF_m2jcPM7E

Can't apply those silly "rules" for such power supply, they're not like desktop power supplies.


@Viperel ... Power supplies often use 220uF 16v rated capacitors for the -12v rail, which is basically not used in modern computers. -12v is only used for serial ports these days, and most motherboards don't have them anymore.
It would make no improvement/benefit

[Viperel]

Re: Any harm in increasing capacitance?

@mariushm would increasing the very small 1uf/2.2uf @ 50V caps with 4.7uf have any beneficial effect inside a SMPSU (as they have really low lifetime in general) or would it be better to replace with stock values?