• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Capacitor voltage rating

M

M1keC

New Member
I'm wondering about voltage ratings on electrolytic capacitors. I know it is possile to use a capacitor with a higher voltage rating - but how much higher is ok? I'm re-capping a Pioneer receiver and there are a number of 100uF caps, some rated 16v, some 25v and some 35v. Now, I have in stock some 100uF/50v caps and I'm wondering if could use these for some or all of the above?
Why did they distinguish between 16v and 25v back in the 70s? Were 25v caps a lot more expensive than 16v? Or were the 16v ones superior in some way?
 
Register to hide this ad
You can go as high as you like for the voltage rating. 25V are bigger and more expensive than 16V, hence 16V would be used where they were adequate.
 
Thanks for that useful information. I guess back in the 70s the difference in cost between 16v and 25v was more significant than today when the difference in cost is only between 1p and a few pennies.
 
Usually up to about 50v the body is the same or very close to the same size. Above that it usually gets bigger. In the past I have simplified parts orders by just getting 35v or 50v parts at a given value to replace multiple voltages at the same value. Most of the big vendors have a price break at 10 and combining a few voltages may push the quantity to the point where it saves money.

A penny per cap times however many caps adds up pretty quick. What makes sense for someone repairing one at home vs manufacturing thousands are pretty different things.
 
M1keC said:
I'm wondering about voltage ratings on electrolytic capacitors. I know it is possile to use a capacitor with a higher voltage rating - but how much higher is ok? I'm re-capping a Pioneer receiver and there are a number of 100uF caps, some rated 16v, some 25v and some 35v. Now, I have in stock some 100uF/50v caps and I'm wondering if could use these for some or all of the above?
Why did they distinguish between 16v and 25v back in the 70s? Were 25v caps a lot more expensive than 16v? Or were the 16v ones superior in some way?
Click to expand...

As long as the materials the cap is made from is the same, there is no problem with substituting a cap with a higher voltage rating.

The differences in voltage ratings are simply to tailor the component to the application. There is no need to put a 50V cap on a 5V rail. I'm sure there are "rules of thumb" to go by when picking voltage ratings based on the maximum voltage the circuit is going to see. Admittedly there isn't much difference between a 16V and a 25V but I suspect it has more to do with the materials and construction techniques available back then.
 
Great. I got a good deal on the 50v 100uF caps so I will use them for the 16v and 25v as well! Thanks guys.
 
M1keC said:
Great. I got a good deal on the 50v 100uF caps so I will use them for the 16v and 25v as well! Thanks guys.
Click to expand...

Keep size in mind. Caps with a higher voltage rating are typically larger than one with a lower rating and may not drop in.
 
You must log in or register to reply here.
Back
Top Bottom