Changing the temp range of a capacitor

[lukesmith]

Hi,

I swapped some blown capacitors in an old (ish) HP L1906 LCD monitor.

It now works great but I have just realised the new capacitors I put in had the wrong max temp range.

The original caps had a range of up to 105 and the new ones are only 85.

I'm just wondering if this is a big issue and I would need to swap them all out again or if these are extreme max ranges and the components are unlikely to get near that kind of temp?

What do you think?

[mariushm]

Re: Changing the temp range of a capacitor

You should change them, when you can.

The higher the temperature rating, the longer the capacitors will work as they should.

The closer the temperature is to their rating, the faster they technical specifications degrade (but very slowly)

Simply put, a 85c capacitor will not live forever as long as the temperature is below 85c, it's not an on/off state. The capacitor is rated for something like 2000h of life at 85c which usually means 4000h at 75c, 8000h at 65c, 16000h at 55 and so on.

The power supply in monitors is usually wrapped in metal with little holes for ventilation so the temperature of the capacitors themselves can often be 50-60c for as long as the monitor runs.

[tom66]

Re: Changing the temp range of a capacitor

More importantly, 85C caps are rarely low-ESR; and will likely fail within short order. What manufacturer and series of capacitor did you use?

[lukesmith]

Re: Changing the temp range of a capacitor

They are Samwha caps.

The monitor lasted many years with CapXcon caps rated at 105C so it would seem that even if they will degrade faster they would still give a at least a couple of years.

Would that sound right?

[mariushm]

Re: Changing the temp range of a capacitor

Samwha are not as bad as Capxon but they're still bad. I'm not sure they will last a year if you use the monitor daily for several hours a day.

Change them as soon as you can.

[lukesmith]

Re: Changing the temp range of a capacitor

What brand would you reccommend? Panasonic?

[mariushm]

Re: Changing the temp range of a capacitor

Panasonic, Nichicon, United Chemi Con (UCC) , Rubycon.. these are all quality brands.

But more importantly, get series from them that have high lifetime rating, along with good specifications.

Panasonic FC, FM , FR , Nichicon HE, HM, HN, UCC KZE, KZ*, LXZ , Rubycon ZLH, ZL, ZLG, YXF, YXG etc etc

[lukesmith]

Re: Changing the temp range of a capacitor

Great thanks