Obsessive component life question

[hamfist]

Will low voltage components in something like an effects pedal be mainly "worn out" over time by the hot/cold cycling of being turned on and off, or by simply the total number of hours being on that they accumulate ?

I ask this question as I do most of my playing at home through my pedalboard into my computer. Often in lots of short segments throughout the day. Is it more wearing on the pedal's electrics to turn my pedalboard on/off each time or to leave the board on all day (thus only hot/cold cycling the components once in the day) ??

[Dad3353]

Good evening, Hamfist...

I would suggest that the mean time between failure (MTBF...) of components in pedals is measured more in centuries than months or years. 'Wearing' won't really apply, whether on, off or cycled in normal domestic or professional situations. There will be some small economy of electricity on turning them off, but some extra wear on the switches. I wouldn't worry about component failure due to being turned on and off, or left on permanently. Consider rather the electricity bill against the convenience to you.
Hope this helps; subject to correction, completion and/or contradiction from others...

[hamfist]

[quote name='Dad3353' timestamp='1381418485' post='2238843']
Good evening, Hamfist...

I would suggest that the mean time between failure (MTBF...) of components in pedals is measured more in centuries than months or years. 'Wearing' won't really apply, whether on, off or cycled in normal domestic or professional situations. There will be some small economy of electricity on turning them off, but some extra wear on the switches. I wouldn't worry about component failure due to being turned on and off, or left on permanently. Consider rather the electricity bill against the convenience to you.
Hope this helps; subject to correction, completion and/or contradiction from others...
[/quote]

THanks "Dad". I did admit it was rather an obsessive query.

[Mr. Foxen]

Switches and pots and joints will go first.

[flyfisher]

The owner will go first.

[hamfist]

So, what I'm getting here is that no-one actually knows the answer to the question ?

It's not actually something I really worry about. Gear goes through my hands quicker than water so I can't imagine ever having a pedal long enough to actually wear it out.

However, I am still interested in an academic way in the major factor(s) in component (ie. resistors and capacitors etc) wearing. I know switches and pots do tend to go first, being the moving parts, but for those that don't move. Anyone know the answer ?

[flyfisher]

I don't know the specific answer for your specific circuit but it can be calculated by a number of tried and tested methods. Reliability engineering is a huge and specialist subject so we're not going to do it justice here but even if you did go to all the time and trouble of doing a reliability analysis you'll end up with something like a Mean Time Between Failure (MTBF) figure that might be useful for a manufacturer but is almost useless for an individual product.

A product with an MTBF of 25 years might be more reliable than one with an MTBF of 10 years but individual samples of either (e.g. the one you happen to own) can still fail next week without affecting the statistical figure of 10 or 25 years.

Circuit design is also a consideration. A mechanical switch will typically have a shorter operational life than, say, a resistor, but only if the circuit design is such that the resistor is operating within its rated conditions (temp, voltage, current, etc). There are plenty of examples of circuit designs that have a "weak component" that often fails, but it's usually a circuit design or component selection issue and can be significantly improved by using a different component.

In other words, it's a hugely complex subject and 'proper' manufacturers spend a great deal of time and money designing and testing the reliability aspects of their products - the more complex the product, the more complex the process, which is usually reflected in the price.

A battery-operated £25 effects pedal is going to be pretty simple and unless you're going to be tap-dancing on the footswitch or using it in the middle of the Sahara desert I'd say you shouldn't be losing any sleep over how turning it on and off might affect its serviceable lifetime.

Just use it and enjoy it (while it still works ).

[Beer of the Bass]

I think with low voltage, low current stuff like pedals, it's more total hours of existence rather than hours of use. There shouldn't be much thermal cycling going on in a pedal, but electrolytic capacitors are only dependable for 20-30 years (unless you're lucky) and pots, switches and jacks are subject to mechanical wear with use. I'd worry more about your power supply getting warm if you leave it on constantly.

[icastle]

[quote name='hamfist' timestamp='1381416097' post='2238777']
Will low voltage components in something like an effects pedal be mainly "worn out" over time by the hot/cold cycling of being turned on and off, or by simply the total number of hours being on that they accumulate ?
[/quote]

That's something more prevalent in applications using AC.

As your power supply is the only thing that gets to see AC, that's the thing that'll die first.

[dincz]

The temperature cycling thing would be more relevant in stuff like power supplies and power amps. There are minute amounts of power and heat in an effects pedal.

[hamfist]

Cool. Great info chaps !